U.S. patent application number 11/752981 was filed with the patent office on 2007-11-29 for percutaneous spinal implants and methods.
Invention is credited to Janna G. Clark, Andrew C. Kohm, Hugues F. MALANDAIN.
Application Number | 20070276493 11/752981 |
Document ID | / |
Family ID | 46327948 |
Filed Date | 2007-11-29 |
United States Patent
Application |
20070276493 |
Kind Code |
A1 |
MALANDAIN; Hugues F. ; et
al. |
November 29, 2007 |
PERCUTANEOUS SPINAL IMPLANTS AND METHODS
Abstract
An apparatus includes a support member and a retention member.
The support member has at least a portion configured to be disposed
between a first spinous process and a second spinous process. The
retention member is movably coupled to an end portion of the
support member. The retention member is configured to displace a
bodily tissue. The retention member is configured to move relative
to the support member from a first position to a second position.
The retention member is configured to limit movement of the support
member along the longitudinal axis and relative to the first
spinous process and the second spinous process when in the second
position.
Inventors: |
MALANDAIN; Hugues F.;
(Mountain View, CA) ; Clark; Janna G.; (Belmont,
CA) ; Kohm; Andrew C.; (Burlingame, CA) |
Correspondence
Address: |
COOLEY GODWARD KRONISH LLP;ATTN: PATENT GROUP
Suite 1100
777 - 6th Street, NW
WASHINGTON
DC
20001
US
|
Family ID: |
46327948 |
Appl. No.: |
11/752981 |
Filed: |
May 24, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11356302 |
Feb 17, 2006 |
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11752981 |
May 24, 2007 |
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11252880 |
Oct 19, 2005 |
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11752981 |
May 24, 2007 |
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11059526 |
Feb 17, 2005 |
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11252880 |
Oct 19, 2005 |
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11356301 |
Feb 17, 2006 |
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11752981 |
May 24, 2007 |
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11252879 |
Oct 19, 2005 |
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11752981 |
May 24, 2007 |
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11252880 |
Oct 19, 2005 |
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11252879 |
Oct 19, 2005 |
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11059526 |
Feb 17, 2005 |
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11252880 |
Oct 19, 2005 |
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11693496 |
Mar 29, 2007 |
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11752981 |
May 24, 2007 |
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11454153 |
Jun 16, 2006 |
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11693496 |
Mar 29, 2007 |
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PCT/US06/05580 |
Feb 17, 2006 |
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11454153 |
Jun 16, 2006 |
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11059526 |
Feb 17, 2005 |
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11454153 |
Jun 16, 2006 |
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11252879 |
Oct 19, 2005 |
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11454153 |
Jun 16, 2006 |
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11252880 |
Oct 19, 2005 |
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11693496 |
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60695836 |
Jul 1, 2005 |
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60695836 |
Jul 1, 2005 |
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60695836 |
Jul 1, 2005 |
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60695836 |
Jul 1, 2005 |
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60695836 |
Jul 1, 2005 |
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Current U.S.
Class: |
623/17.11 ;
606/249; 606/66 |
Current CPC
Class: |
A61B 17/7065 20130101;
A61B 2017/00557 20130101; A61B 2017/0256 20130101; A61B 17/025
20130101 |
Class at
Publication: |
623/017.11 ;
606/061; 606/066; 606/069 |
International
Class: |
A61F 2/44 20060101
A61F002/44; A61B 17/58 20060101 A61B017/58 |
Claims
1. An apparatus comprising: a first member having a first surface
and a second surface, the second surface offset from a longitudinal
axis of the first member by a non-zero angle, at least a portion of
the first surface configured to engage a spinous process; and a
second member rotatably coupled to a distal end of the first
member, the second member configured to move relative to the first
member between a first position and a second position, at least a
portion of a surface of the second member being disposed adjacent
at least a portion of the second surface of the first member when
the second member is in the first position, the portion of the
surface of the second member being disposed apart from the portion
of the second surface of the first member when the second member is
in the second position, the portion of the surface of the second
member configured to limit movement of the first member along the
longitudinal axis and relative to the spinous process when the
second member is in the second position.
2. The apparatus of claim 1, wherein the first surface of the first
member is substantially parallel to the longitudinal axis of the
first member.
3. The apparatus of claim 1, wherein the surface of the second
member is substantially parallel to the second surface of the first
member.
4. The apparatus of claim 1, wherein the second surface of the
first member is disposed at the distal end of the first member.
5. The apparatus of claim 1, wherein the surface of the second
member is in contact with the portion of the second surface of the
first member when the second member is in the first position.
6. The apparatus of claim 1, wherein the portion of the surface of
the second member is configured to engage the spinous process to
limit movement of the first member along the longitudinal axis and
relative to the spinous process.
7. The apparatus of claim 1, wherein the second member is
configured to rotate relative to the first member from the first
position to the second position about an axis substantially
parallel to the longitudinal axis of the first member.
8. The apparatus of claim 1, wherein: the spinous process is a
first spinous process; the first member and the second member are
configured to be inserted percutaneously such that the portion of
the first surface of the first member is between the first spinous
process and a second spinous process; and the second member is
configured to move from the first position to the second position
after the at least the portion of the first member is disposed
between the first spinous process and the second spinous
process.
9. The apparatus of claim 1, wherein: the second surface of the
first member has an area; and the surface of the second member has
an area, the area of the surface of the second member being within
the area of the second surface of the first member when projected
on a plane substantially normal to the longitudinal axis and when
the second member is in the first position, a portion of the area
of the surface of the second member being outside of the area of
the second surface of the first member when projected on the plane
substantially normal to the longitudinal axis and when the second
member is in the second position.
10. The apparatus of claim 1, wherein a portion of the surface of
the second member and a portion of the first surface of the first
member collectively form a portion of a saddle configured to
receive a portion of the spinous process when the second member is
in the second position.
11. The apparatus of claim 1, wherein the surface of the second
member is a first surface, the second member including a second
surface substantially parallel to the first surface of the first
member, the apparatus further comprising: a locking member disposed
within the first member and configured to engage the first surface
of the second member when the second member is in the first
position, at least a portion of the locking member disposed outside
of the first member and configured to engage the second surface of
the second member when the second member is in the second position;
and a biasing member disposed within the first member, the biasing
member configured to bias the locking member such that the portion
of the locking member is disposed outside of the first member.
12. The apparatus of claim 1, wherein: the surface of the second
member is a first surface; and the second member includes a second
surface having a curved shape asymmetrical about the longitudinal
axis.
13. The apparatus of claim 1, wherein: the surface of the second
member is a first surface; and the second member includes a second
surface configured to dilate a bodily tissue.
14. The apparatus of claim 1, wherein: the surface of the second
member is a first surface; and the second member includes a second
surface configured to distract a space between the spinous process
and an adjacent spinous process.
15. An apparatus, comprising: a support member having at least a
portion configured to be disposed between a first spinous process
and a second spinous process; and a retention member movably
coupled to an end portion of the support member, the retention
member configured to displace a bodily tissue, the retention member
configured to move relative to the support member from a first
position to a second position, the retention member configured to
limit movement of the support member along a longitudinal axis of
the support member and relative to the first spinous process and
the second spinous process when in the second position.
16. The apparatus of claim 15, wherein the retention member is
configured to rotate about an axis substantially parallel to a
longitudinal axis of the support member.
17. The apparatus of claim 15, wherein: a portion of the retention
member is disposed within the support member when the retention
member is in the first position; and the portion of the retention
member is disposed outside of the support member when the retention
member is in the second position.
18. The apparatus of claim 15, wherein: the end portion of the
support member has a cross-sectional area normal to the
longitudinal axis of the support member; and the retention member
has a cross-sectional area normal to the longitudinal axis of the
support member, the cross-sectional area of the retention member
being within the cross-sectional area of the end portion of the
support member when projected on a plane substantially normal to
the longitudinal axis and when the retention member is in the first
position, a portion of the cross-sectional area of the retention
member being outside of the cross-sectional area of the end portion
of the support member when projected on the plane substantially
normal to the longitudinal axis and when the retention member is in
the second position.
19. The apparatus of claim 15, wherein: the support member and the
retention member are configured to be inserted between the first
spinous process and the second spinous process percutaneously; and
the retention member is configured to move from the first position
to the second position after the support member is disposed between
the first spinous process and the second spinous process.
20. The apparatus of claim 15, wherein the support member and the
retention member are configured to be inserted between the first
spinous process and the second spinous process percutaneously in a
direction along the longitudinal axis of the support member.
21. The apparatus of claim 15, wherein: the support member is
tapered such that a size of a distal end portion of the support
member along an axis substantially normal to the longitudinal axis
is less than a size of a proximal end portion of the support member
along the axis substantially normal to the longitudinal axis; and
the retention member is movably coupled to the distal end portion
of the support member.
22. The apparatus of claim 15, wherein a portion of the retention
member and a portion of the support member collectively form a
portion of a saddle configured to receive a portion of the first
spinous process when the retention member is in the second
position.
23. The apparatus of claim 15, wherein the portion of the support
member is configured to engage the first spinous process and the
second spinous process upon spinal extension.
24. The apparatus of claim 15, wherein the retention member is
configured to repeatedly move between the first position and the
second position.
25. The apparatus of claim 15, wherein the retention member is a
first retention member and the end portion of the support member is
a distal end portion, the apparatus further comprising: a second
retention member movably coupled to a proximal end portion of the
support member, the second retention member configured to rotate
relative to the support member from a first position to a second
position about the axis substantially parallel to the longitudinal
axis of the support member, the second retention member configured
to limit movement of the support member along the longitudinal axis
and relative to the first spinous process and the second spinous
process when in the second position.
26. The apparatus of claim 15, further comprising a locking member
configured to releasably maintain the retention member in the
second position.
27. The apparatus of claim 15, further comprising: a locking member
disposed within the support member and configured to engage a first
surface of the retention member when the retention member is in the
first position such that the retention member is maintained in the
first position, at least a portion of the locking member disposed
outside of the support member and configured to engage a second
surface of the retention member when the retention member is in the
second position such that the retention member is maintained in the
second position, the second surface different than the first
surface.
28. The apparatus of claim 15, further comprising: a locking member
disposed within the support member and configured to engage a first
surface of the retention member when the retention member is in the
first position such that the retention member is maintained in the
first position, at least a portion of the locking member disposed
outside of the support member and configured to engage a second
surface of the retention member when the retention member is in the
second position such that the retention member is maintained in the
second position, the second surface different than the first
surface; and a biasing member disposed within the support member,
the biasing member configured to bias the locking member in a
direction such that the at least the portion of the locking member
is disposed outside of the support member.
29. The apparatus of claim 15, wherein the retention member has an
outer surface that is curved asymmetrically about the longitudinal
axis.
30. The apparatus of claim 15, wherein the retention member has a
tapered end portion configured to dilate the bodily tissue.
31. the apparatus of claim 15, wherein the retention member is
configured to distract a space between the first spinous process
and the second spinous process.
32. An apparatus comprising: a support member having at least a
portion configured to engage adjacent spinous processes, a distal
end of the support member having a cross-sectional area normal to a
longitudinal axis of the support member; and a retention member
rotatably coupled to the distal end of the support member, the
retention member having a cross-sectional area normal to the
longitudinal axis of the support member, the retention member
configured to rotate relative to the support member about an axis
substantially parallel to the longitudinal axis of the support
member from a first position to a second position, the retention
member configured to limit movement of the support member along the
longitudinal axis and relative to the first spinous process and the
second spinous process when in the second position, the
cross-sectional area of the retention member being within the
cross-sectional area of the distal end of the support member when
projected on a plane substantially normal to the longitudinal axis
and when the retention member is in the first position, a portion
of the cross-sectional area of the retention member being outside
of the cross-sectional area of the distal end of the support member
when projected on the plane substantially normal to the
longitudinal axis and when the retention member is in the second
position.
33. The apparatus of claim 32, wherein: the support member and the
retention member are configured to be inserted between the first
spinous process and the second spinous process percutaneously; and
the retention member is configured to rotate from the first
position to the second position after the support member is
disposed between the first spinous process and the second spinous
process.
34. The apparatus of claim 32, wherein the support member is
tapered such that a size of the distal end portion of the support
member along an axis substantially normal to the longitudinal axis
is less than a size of a proximal end portion of the support member
along the axis substantially normal to the longitudinal axis.
35. The apparatus of claim 32, wherein a portion of the retention
member and a portion of the support member collectively form a
portion of a saddle configured to receive the first spinous process
when the retention member is in the second position.
36. The apparatus of claim 32, wherein: a proximal end of the
retention member is coupled to the distal end of the support
member; and the cross-sectional area of the retention member is
coincident with the proximal end of the retention member.
37. The apparatus of claim 32, wherein the retention member is
configured to repeatedly move between the first position and the
second position.
38. The apparatus of claim 32, wherein the retention member is a
first retention member, the apparatus further comprising: a second
retention member rotatably coupled to a proximal end portion of the
support member, the second retention member configured to rotate
relative to the support member from a first position to a second
position about an axis substantially parallel to the longitudinal
axis of the support member, the second retention member configured
to limit movement of the support member along the longitudinal axis
and relative to the first spinous process and the second spinous
process when in the second position.
39. The apparatus of claim 32, further comprising a locking member
configured to reversibly maintain the retention member in the
second position.
40. The apparatus of claim 32, further comprising: a locking member
disposed within the support member and configured to engage a
proximal surface of the retention member when the retention member
is in the first position such that the retention member is
maintained in the first position, at least a portion of the locking
member disposed outside of the support member and configured to
engage an outer surface of the retention member when the retention
member is in the second position such that the retention member is
maintained in the second position; and a biasing member disposed
within the support member, the biasing member configured to bias
the locking member in a direction such that the at least the
portion of the locking member is disposed outside of the support
member.
41. An apparatus comprising: a support member having at least a
portion configured to engage adjacent spinous processes, a distal
end of the support member having a first dimension along a first
axis substantially normal to a longitudinal axis of the support
member and a second dimension along a second axis, the second axis
being substantially normal to the longitudinal axis and the first
axis, the second dimension greater than the first dimension; and a
retention member movably coupled to the distal end of the support
member, the retention member configured to displace a bodily
tissue, the retention member configured to move relative to the
support member from a first position to a second position, the
retention member having a first dimension along the first axis and
a second dimension along the second axis, the first dimension of
the retention member being greater than the second dimension of the
support member and no greater than the first dimension of the
support member, the second dimension of the retention member being
no greater than the second dimension of the support member.
42. The apparatus of claim 41, wherein the retention member is
configured to rotate relative to the support member from the first
position to the second position about an axis substantially
parallel to the longitudinal axis of the support member.
43. The apparatus of claim 41, wherein: the first dimension of the
retention member is aligned with the first dimension of the support
member when the retention member is in the first position; and the
first dimension of the retention member is aligned with the second
dimension of the support member when the retention member is in the
second position.
44. The apparatus of claim 41, wherein: the first dimension of the
retention member is substantially equal to the first dimension of
the support member; and the second dimension of the retention
member is substantially equal to the second dimension of the
support member.
45. The apparatus of claim 41, wherein the retention member is
configured to repeatedly move between the first position and the
second position.
46. The apparatus of claim 41, wherein the retention member is a
first retention member, the apparatus further comprising: a second
retention member movably coupled to a proximal end portion of the
support member, the second retention member configured to rotate
relative to the support member from a first position to a second
position about an axis substantially parallel to the longitudinal
axis of the support member, the second retention member configured
to limit movement of the support member along the longitudinal axis
and relative to the first spinous process and the second spinous
process when in the second position.
47. The apparatus of claim 41, further comprising: a locking member
disposed within the support member and configured to engage a
proximal surface of the retention member when the retention member
is in the first position such that the retention member is
maintained in the first position, at least a portion of the locking
member disposed outside of the support member and configured to
engage an outer surface of the retention member when the retention
member is in the second position such that the retention member is
maintained in the second position; and a biasing member disposed
within the support member, the biasing member configured to bias
the locking member in a direction such that the at least the
portion of the locking member is disposed outside of the support
member.
48. The apparatus of claim 41, wherein the retention member has a
tapered end portion configured to dilate the bodily tissue.
49. the apparatus of claim 41, wherein the retention member is
configured to distract a space between the first spinous process
and the second spinous process.
50. An apparatus comprising: a support member configured to be
disposed between a first spinous process and a second spinous
process; a retention member movably coupled to a distal end of the
support member, the retention member configured to move from a
first position to a second position to limit movement of the
support member along a longitudinal axis and relative to the first
spinous process and the second spinous process; and a locking
member disposed within the support member and configured to engage
a first surface of the retention member when the retention member
is in the first position such that the retention member is
maintained in the first position, at least a portion of the locking
member disposed outside of the support member and configured to
engage a second surface of the retention member when the retention
member is in the second position such that the retention member is
maintained in the second position, the second surface different
than the first surface.
51. The apparatus of claim 50, wherein the retention member is
configured to rotate relative to the support member from the first
position to the second position about an axis substantially
parallel to the longitudinal axis of the support member.
52. The apparatus of claim 50, wherein: the support member and the
retention member are configured to be inserted between the first
spinous process and the second spinous process percutaneously; and
the retention member is configured to move from the first position
to the second position after the support member is disposed between
the first spinous process and the second spinous process.
53. The apparatus of claim 50, wherein: the distal end of the
support member has a cross-sectional area normal to a longitudinal
axis of the support member; and the retention member has a
cross-sectional area normal to the longitudinal axis of the support
member, the cross-sectional area of the retention member being
within the cross-sectional area of the distal end of the support
member when projected on a plane substantially normal to the
longitudinal axis and when the retention member is in the first
position, a portion of the cross-sectional area of the retention
member being outside of the cross-sectional area of the distal end
of the support member when projected on the plane substantially
normal to the longitudinal axis and when the retention member is in
the second position.
54. The apparatus of claim 50, wherein the retention member is
configured to repeatedly move between the first position and the
second position.
55. The apparatus of claim 50, wherein: the first surface of the
retention member includes a recessed portion configured to receive
a first portion of the locking member when the retention member is
in the first position; and the second surface of the retention
member includes a recessed portion configured to receive a second
portion of the locking member when the retention member is in the
second position.
56. The apparatus of claim 50, wherein the retention member is a
first retention member, the apparatus further comprising: a second
retention member movably coupled to a proximal end of the support
member, the second retention member configured to rotate relative
to the support member from a first position to a second position
about an axis substantially parallel to a longitudinal axis of the
support member, the second retention member configured to limit
movement of the support member along the longitudinal axis and
relative to the first spinous process and the second spinous
process when in the second position.
57. The apparatus of claim 50, further comprising: a biasing member
disposed within the support member, the biasing member configured
to bias the locking member in a direction such that the at least
the portion of the locking member is disposed outside of the
support member.
58. A method comprising: disposing at least a portion of an implant
between adjacent spinous processes, the implant including a support
member and a retention member movably coupled to the support
member; rotating the retention member from a first position to a
second position such that the retention member retains a portion of
the implant between the adjacent spinous processes; and locking
reversibly the retention member in the second position.
59. The method of claim 58, wherein the disposing includes
inserting the implant percutaneously via a lateral access path
including a portion at the sides of the adjacent spinous
processes.
60. The method of claim 58, wherein: the retention member is
disposed within the support member when in the first position; and
a portion of the retention member is disposed outside of the
support member when in the second position.
61. The method of claim 58, wherein the rotating includes rotating
the retention member about an axis substantially parallel to a
longitudinal axis of the support member.
62. The method of claim 58, wherein: an end portion of the support
member has a cross-sectional area normal to the longitudinal axis
of the support member; the retention member has a cross-sectional
area normal to the longitudinal axis of the support member, the
cross-sectional area of the retention member being within the
cross-sectional area of the distal end of the support member
projected on a plane substantially normal to the longitudinal axis
and when the retention member is in the first position; and the
rotating includes rotating the retention member such that a portion
of the cross-sectional area of the retention member is outside of
the cross-sectional area of the distal end of the support member
when projected on the plane substantially normal to the
longitudinal axis.
63. The method of claim 58, wherein the disposing includes
disposing the implant such that a portion of the retention member
distracts a space between the adjacent spinous processes.
64. The method of claim 58, further comprising distracting a space
between the adjacent spinous processes before the disposing.
65. An apparatus, comprising: a support member having at least a
portion configured to be disposed between a first spinous process
and a second spinous process; a first retention member movably
coupled to a first end portion of the support member; and a second
retention member movably coupled to a second end portion of the
support member, the second retention member coupled to the first
retention member such that the first retention member and the
second retention member are configured to collectively move
relative to the support member from a first position to a second
position, the first retention member and the second retention
member configured to limit movement of the support member relative
to the first spinous process and the second spinous process when in
the second position.
66. The apparatus of claim 65, wherein the first retention member
and the second retention member are configured to collectively
rotate relative to the support member from the first position to
the second position.
67. The apparatus of claim 65, wherein the first retention member
and the second retention member are configured to collectively
rotate relative to the support member about an axis substantially
parallel to the longitudinal axis of the support member.
68. The apparatus of claim 65, wherein the first end portion of the
support member has a cross-sectional area normal to the
longitudinal axis of the support member; the first retention member
has a cross-sectional area normal to the longitudinal axis of the
support member; the second end portion of the support member has a
cross-sectional area normal to the longitudinal axis of the support
member; and the second retention member has a cross-sectional area
normal to the longitudinal axis of the support member, the
cross-sectional area of the first retention member being within the
cross-sectional area of the first end portion of the support member
when projected on a plane substantially normal to the longitudinal
axis and when the first retention member is in the first position,
a portion of the cross-sectional area of the first retention member
being outside of the cross-sectional area of the first end portion
of the support member when projected on the plane substantially
normal to the longitudinal axis and when the first retention member
is in the second position, the cross-sectional area of the second
retention member being within the cross-sectional area of the
second end portion of the support member when projected on a plane
substantially normal to the longitudinal axis and when the second
retention member is in the first position, a portion of the
cross-sectional area of the second retention member being outside
of the cross-sectional area of the second end portion of the
support member when projected on the plane substantially normal to
the longitudinal axis and when the second retention member is in
the second position.
69. The apparatus of claim 65, wherein: the support member, the
first retention member and the second retention member are
configured to be inserted between the first spinous process and the
second spinous process percutaneously; and the first retention
member and the second retention member are configured to
collectively move relative to the support member from the first
position to the second position after the support member is
disposed between the first spinous process and the second spinous
process.
70. The apparatus of claim 65, wherein a portion of the support
member, a portion of the first retention member and a portion of
the second retention member collectively form a portion of a saddle
configured to receive a portion of the first spinous process when
the first retention member and the second retention member are in
the second position.
71. The apparatus of claim 65, wherein the first retention member
and the second retention member are configured to repeatedly move
between the first position and the second position.
72. The apparatus of claim 65, further comprising a locking member
configured to releasably maintain the first retention member and
the second retention member in the second position.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a
continuation-in-part of U.S. patent application Ser. No.
11/356,302, entitled "Percutaneous Spinal Implants and Methods,"
filed Feb. 17, 2006, which claims priority to U.S. Provisional
Application Ser. No. 60/695,836, entitled "Percutaneous Spinal
Implants and Methods," filed Jul. 1, 2005, and which is a
continuation-in-part of U.S. patent application Ser. No.
11/252,880, entitled "Percutaneous Spinal Implants and Methods,"
filed Oct. 19, 2005, which is a continuation-in-part of U.S. patent
application Ser. No. 11/059,526, entitled "Apparatus and Method for
Treatment of Spinal Conditions," filed Feb. 17, 2005, and which
claims priority to U.S. Provisional Application Ser. No.
60/695,836, entitled "Percutaneous Spinal Implants and Methods,"
filed Jul. 1, 2005. Each of the above-identified applications is
incorporated herein by reference in its entirety.
[0002] This application also claims priority to and is a
continuation-in-part of U.S. patent application Ser. No.
11/356,301, entitled "Percutaneous Spinal Implants and Methods,"
filed Feb. 17, 2006, which claims priority to U.S. Provisional
Application Ser. No. 60/695,836, entitled "Percutaneous Spinal
Implants and Methods," filed Jul. 1, 2005, and which is a
continuation-in-part of U.S. patent application Ser. Nos.
11/252,879 and 11/252,880, each entitled "Percutaneous Spinal
Implants and Methods," and filed October 19, each of which is a
continuation-in-part of U.S. patent application Ser. No.
11/059,526, entitled "Apparatus and Method for Treatment of Spinal
Conditions," filed Feb. 17, 2005. Each of the above-identified
applications is incorporated herein by reference in its
entirety.
[0003] This application also claims priority to and is a
continuation-in-part of U.S. patent application Ser. No. 11/693,496
entitled "Percutaneous Spinal Implants and Methods," filed Mar. 29,
2007, which is a continuation-in-part of U.S. patent application
Ser. No. 11/454,153, entitled "Percutaneous Spinal Implants and
Methods," filed Jun. 16, 2006, which is a continuation-in-part of
International Patent Application No. PCT/US2006/005580, entitled
"Percutaneous Spinal Implants and Methods," filed Feb. 17, 2006,
and which is a continuation-in-part of U.S. patent application Ser.
No. 11/059,526, entitled "Apparatus and Method for Treatment of
Spinal Conditions," filed Feb. 17, 2005, and which is a
continuation-in-part of U.S. patent application Ser. No.
11/252,879, entitled "Percutaneous Spinal Implants and Methods,"
filed Oct. 19, 2005, which claims priority to U.S. Provisional
Application Ser. No. 60/695,836, entitled "Percutaneous Spinal
Implants and Methods," filed Jul. 1, 2005, and which is a
continuation-in-part of U.S. patent application Ser. No.
11/252,880, entitled "Percutaneous Spinal Implants and Methods,"
filed Oct. 19, 2005, which claims priority to U.S. Provisional
Application Ser. No. 60/695,836, entitled "Percutaneous Spinal
Implants and Methods," filed Jul. 1, 2005. Each of the
above-identified applications is incorporated herein by reference
in its entirety.
[0004] This application is related to U.S. patent application
Attorney Docket Nos. KYPH-001/22US-305363-2140,
KYPH-001/23US-305363-2139 and KYPH-001/24US-305363-2163 each
entitled "Percutaneous Spinal Implants and Methods," filed on the
same date, each of which is incorporated herein by reference in
their entirety.
BACKGROUND
[0005] The invention relates generally to the treatment of spinal
conditions, and more particularly, to the treatment of spinal
compression using percutaneous spinal implants for implantation
between adjacent spinous processes.
[0006] A back condition that impacts many individuals is spinal
stenosis. Spinal stenosis is a progressive narrowing of the spinal
canal that causes compression of the spinal cord. Each vertebra in
the spinal column has an opening that extends through it. The
openings are aligned vertically to form the spinal canal. The
spinal cord runs through the spinal canal. As the spinal canal
narrows, the spinal cord and nerve roots extending from the spinal
cord and between adjacent vertebrae are compressed and may become
inflamed. Spinal stenosis can cause pain, weakness, numbness,
burning sensations, tingling, and in particularly severe cases, may
cause loss of bladder or bowel function, or paralysis. The legs,
calves and buttocks are most commonly affected by spinal stenosis,
however, the shoulders and arms may also be affected.
[0007] Mild cases of spinal stenosis may be treated with rest or
restricted activity, non-steroidal anti-inflammatory drugs (e.g.,
aspirin), corticosteroid injections (epidural steroids), and/or
physical therapy. Some patients find that bending forward, sitting
or lying down may help relieve the pain. This may be due to bending
forward creates more vertebral space, which may temporarily relieve
nerve compression. Because spinal stenosis is a progressive
disease, the source of pressure may have to be surgically corrected
(decompressive laminectomy) as the patient has increasing pain. The
surgical procedure can remove bone and other tissues that have
impinged upon the spinal canal or put pressure on the spinal cord.
Two adjacent vertebrae may also be fused during the surgical
procedure to prevent an area of instability, improper alignment or
slippage, such as that caused by spondylolisthesis. Surgical
decompression can relieve pressure on the spinal cord or spinal
nerve by widening the spinal canal to create more space. This
procedure requires that the patient be given a general anesthesia
as an incision is made in the patient to access the spine to remove
the areas that are contributing to the pressure. This procedure,
however, may result in blood loss and an increased chance of
significant complications, and usually results in an extended
hospital stay.
[0008] Minimally-invasive procedures have been developed to provide
access to the space between adjacent spinous processes such that
major surgery is not required. Such known procedures, however, may
not be suitable in conditions where the spinous processes are
severely compressed. Moreover, such procedures typically involve
large or multiple incisions.
[0009] Thus, a need exists for improvements in the treatment of
spinal conditions such as spinal stenosis.
SUMMARY OF THE INVENTION
[0010] Medical devices and related methods for the treatment of
spinal conditions are described herein. In some embodiments, an
apparatus includes a support member and a retention member. The
support member has at least a portion configured to be disposed
between a first spinous process and a second spinous process. The
retention member is movably coupled to an end portion of the
support member. The retention member is configured to displace a
bodily tissue. The retention member is configured to move relative
to the support member from a first position to a second position.
The retention member is configured to limit movement of the support
member along a longitudinal axis of the support member and relative
to the first spinous process and the second spinous process when in
the second position. In some embodiments, for example, the
retention member and a portion of the support member collectively
form a portion of a saddle configured to receive a portion of the
first spinous process when the retention member is in the second
position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic illustration of a posterior view of a
medical device according to an embodiment of the invention in a
first configuration adjacent two adjacent spinous processes.
[0012] FIG. 2 is a schematic illustration of a posterior view of a
medical device according to an embodiment of the invention in a
second configuration adjacent two adjacent spinous processes.
[0013] FIG. 3 is a schematic illustration of a deforming element
according to an embodiment of the invention in a first
configuration.
[0014] FIG. 4 is a schematic illustration of a side view of the
expanding element illustrated in FIG. 3.
[0015] FIG. 5 is a side view of a medical device according to an
embodiment of the invention in a first configuration.
[0016] FIG. 6 is a side view of the medical device illustrated in
FIG. 5 in a second configuration.
[0017] FIG. 7 is a perspective view of a medical device according
to an embodiment of the invention in a first configuration.
[0018] FIG. 8 is a posterior view of a medical device according to
an embodiment of the invention, a portion of which is in a second
configuration.
[0019] FIG. 9 is a posterior view of the medical device illustrated
in FIG. 7 fully deployed in the second configuration.
[0020] FIG. 10 is a front plan view of the medical device
illustrated in FIG. 7 in the second configuration.
[0021] FIG. 11 is a perspective view of an implant expansion device
according to an embodiment of the invention.
[0022] FIG. 12 is an alternative perspective view of the implant
expansion device illustrated in FIG. 11.
[0023] FIG. 13 is a perspective view of a portion of the implant
expansion device illustrated in FIG. 11.
[0024] FIG. 14 is a cross-sectional view of a portion of the device
illustrated in FIG. 11, taken along line A-A in FIG. 11.
[0025] FIG. 15 is a cross-sectional view of a portion of the device
illustrated in FIG. 11 in a first configuration, taken along line
B-B in FIG. 11.
[0026] FIG. 16 is a cross-sectional view of a portion of the device
illustrated in FIG. 11 in a second configuration, taken along line
C-C in FIG. 11.
[0027] FIG. 17 is a side perspective view of an implant according
to an embodiment of the invention shown in a collapsed
configuration.
[0028] FIG. 18 is a cross-sectional view of the implant of FIG. 17
taken along line 18-18.
[0029] FIG. 19 is a side perspective view of the implant of FIG. 17
shown in an expanded configuration.
[0030] FIG. 20 is a rear perspective view of the implant of FIG. 17
shown in a collapsed configuration.
[0031] FIG. 21 is cross-sectional view of the implant of FIG. 17
shown in a collapsed configuration taken along line 21-21.
[0032] FIG. 22 is a rear perspective view of an implant according
to an embodiment of the invention shown in a collapsed
configuration.
[0033] FIG. 23 is a cross-sectional view of the implant of FIG. 22
shown in a collapsed configuration.
[0034] FIG. 24 is a perspective view of the implant of FIG. 22 in a
collapsed configuration disposed on an expansion tool according to
an embodiment of the invention.
[0035] FIG. 25 is a perspective view of the implant and the
expansion tool of FIG. 24 taken along region 25.
[0036] FIG. 26 is a side cross-sectional view of the implant and
the expansion tool of FIG. 24.
[0037] FIG. 27 is a side cross-sectional view of the implant and
the expansion tool as shown in FIG. 26 taken along region 27.
[0038] FIG. 28 is a perspective view of the implant of FIG. 22 in
an expanded configuration disposed on an expansion tool according
to an embodiment of the invention.
[0039] FIG. 29 is a perspective view of the implant and the
expansion tool of FIG. 28 taken along region 29.
[0040] FIG. 30 is a side cross-sectional view of the implant and
the expansion tool of FIG. 28.
[0041] FIG. 31 is a side cross-sectional view of the implant and
the expansion tool as shown in FIG. 30 taken along region 31.
[0042] FIGS. 32-35 are schematic illustrations of a posterior view
of a medical device according to an embodiment of the invention in
a first configuration (FIG. 32), a second (FIGS. 33 and 35)
configuration and a third configuration (FIG. 34).
[0043] FIGS. 36-38 are schematic illustrations of a posterior view
of a medical device according to an embodiment of the invention in
a first configuration, a second configuration and a third
configuration, respectively.
[0044] FIGS. 39-44 are posterior views of a medical device
according to an embodiment of the invention inserted between
adjacent spinous processes in a first lateral positions and a
second lateral position.
[0045] FIG. 45 is a lateral view of the medical device illustrated
in FIGS. 39-44 inserted between adjacent spinous processes in a
second configuration.
[0046] FIG. 46 is a lateral view of a medical device according to
an embodiment of the invention inserted between adjacent spinous
processes in a second configuration.
[0047] FIGS. 47 and 48 are front views of a medical device
according to an embodiment of the invention in a first
configuration and a second configuration, respectively.
[0048] FIG. 49 is a schematic illustration of a posterior view of a
medical device according to an embodiment of the invention in a
first configuration disposed between two adjacent spinous
processes.
[0049] FIG. 50 is a schematic illustration of a posterior view of a
medical device according to an embodiment of the invention in a
second configuration disposed between two adjacent spinous
processes.
[0050] FIGS. 51 and 52 are perspective views of a medical device
according to an embodiment of the invention in a first
configuration and a second configuration, respectively.
[0051] FIG. 53 is a posterior view of the medical device
illustrated in FIGS. 51 and 52 disposed between adjacent spinous
processes in a second configuration.
[0052] FIG. 54 is a lateral view taken from a proximal perspective
A-A of the medical device illustrated in FIG. 53 disposed between
adjacent spinous processes in a second configuration.
[0053] FIG. 55 is a cross-sectional front view of the medical
device illustrated in FIGS. 51 and 52 in a second
configuration.
[0054] FIG. 56 is a cross-sectional plan view taken along section
A-A of the medical device illustrated in FIGS. 51 and 52 in a
second configuration.
[0055] FIG. 57 is a cross-sectional front view of a medical device
according to an embodiment of the invention in a second
configuration.
[0056] FIGS. 58 and 59 are cross-sectional plan views taken along
section A-A of the medical device illustrated in FIG. 57 in a
second configuration and a first configuration, respectively.
[0057] FIG. 60 is a cross-sectional front view of a medical device
according to an embodiment of the invention in a second
configuration.
[0058] FIGS. 61 through 63 are cross-sectional plan views taken
along section A-A of the medical device illustrated in FIG. 60 in a
second configuration, a first configuration, and a third
configuration respectively.
[0059] FIGS. 64 and 65 are cross-sectional front views of a medical
device according to an embodiment of the invention in a second
configuration and a first configuration, respectively.
[0060] FIG. 66 is a cross-sectional front view of a medical device
according to an embodiment of the invention in a second
configuration.
[0061] FIG. 67 is a cross-sectional plan view taken along section
A-A of the medical device illustrated in FIG. 66 in a second
configuration.
[0062] FIGS. 68 and 69 are perspective views of a medical device
according to an embodiment of the invention in a second
configuration and a first configuration, respectively.
[0063] FIGS. 70 and 71 are lateral views of a medical device
according to an embodiment of the invention in a first
configuration and a second configuration, respectively.
[0064] FIGS. 72 and 73 are perspective views of the medical device
illustrated in FIGS. 70 and 71 in a first configuration and a
second configuration, respectively.
[0065] FIG. 74 is a cross-sectional plan view of the medical device
illustrated in FIGS. 70 and 71 in a second configuration.
[0066] FIG. 75 is a posterior view of a portion of a medical device
according to an embodiment of the invention disposed within a body
between a pair of spinous processes.
[0067] FIG. 76 is a side view of the portion of medical device
shown in FIG. 75 taken along the lateral axis L.sub.L.
[0068] FIGS. 77 and 78 are a side view and a top plan view,
respectively, of the portion of medical device shown in FIG.
75.
[0069] FIGS. 79 and 80 are a side view and a top plan view,
respectively, of a portion of a medical device according to an
embodiment of the invention.
[0070] FIG. 81 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention disposed between a first spinous process and second
spinous process.
[0071] FIG. 82 is a schematic illustration of a lateral view of the
implant shown in FIG. 81 in the first configuration.
[0072] FIG. 83 is a schematic illustration of a posterior view of
the implant shown in FIG. 81 in a second configuration.
[0073] FIG. 84 is a schematic illustration of a lateral view of the
implant shown in FIG. 81 in a second first configuration.
[0074] FIG. 85 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention disposed between a first spinous process and second
spinous process.
[0075] FIG. 86 is a schematic illustration of a side view of the
implant shown in FIG. 85 in the first configuration.
[0076] FIG. 87 is a schematic illustration of a lateral
cross-sectional view of the implant shown in FIG. 85 in the first
configuration taken along line A-A.
[0077] FIG. 88 is a schematic illustration of a posterior view of
the implant shown in FIG. 85 in a second configuration.
[0078] FIG. 89 is a schematic illustration of a side view of the
implant shown in FIG. 85 in the second configuration.
[0079] FIG. 90 is a schematic illustration of a lateral
cross-sectional view of the implant shown in FIG. 85 in the second
configuration taken along line A-A.
[0080] FIG. 91 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention disposed between a first spinous process and second
spinous process.
[0081] FIG. 92 is a schematic illustration of a side view of the
implant shown in FIG. 91 in the first configuration.
[0082] FIG. 93 is a schematic illustration of a posterior view of
the implant shown in FIG. 91 in a second configuration.
[0083] FIG. 94 is a schematic illustration of a side view of the
implant shown in FIG. 91 in the second configuration.
[0084] FIG. 95 is a perspective view of an implant according to an
embodiment of the invention in a first configuration.
[0085] FIG. 96 is a perspective view of the implant shown in FIG.
95 in a second configuration.
[0086] FIG. 97 is a perspective view of a support member of the
implant shown in FIG. 95.
[0087] FIG. 98 is a perspective view of a distal retention member
of the implant shown in FIG. 95.
[0088] FIG. 99 is a perspective view of a proximal retention member
of the implant shown in FIG. 95.
[0089] FIG. 100 is a perspective view of an implant according to an
embodiment of the invention in a first configuration.
[0090] FIG. 101 is a front view of the implant shown in FIG. 100 in
the first configuration.
[0091] FIG. 102 is a bottom view of the implant shown in FIG. 100
in the first configuration.
[0092] FIG. 103 is a perspective view of the implant shown in FIG.
100 in a second configuration.
[0093] FIG. 104 is a front view of the implant shown in FIG. 100 in
the second configuration.
[0094] FIG. 105 is a bottom view of the implant shown in FIG. 100
in the second configuration.
[0095] FIG. 106 is a cross-sectional perspective view of a
deployment tool according to an embodiment of the invention.
[0096] FIG. 107 is a cross-sectional front view of the deployment
tool shown in FIG. 106 engaging a proximal portion of the implant
shown in FIG. 100.
[0097] FIG. 108 is a perspective view of the deployment tool shown
in FIG. 106 engaging the proximal portion of the implant shown in
FIG. 100 in the first configuration.
[0098] FIG. 109 is a perspective view of the deployment tool shown
in FIG. 106 engaging the proximal portion the implant shown in FIG.
100 in the second configuration.
[0099] FIG. 110 is a cross-sectional front view of the deployment
tool shown in FIG. 106 engaging a distal portion the implant shown
in FIG. 100.
[0100] FIG. 111 is a perspective view of the deployment tool shown
in FIG. 106 engaging the distal portion the implant shown in FIG.
100 in the second configuration.
[0101] FIG. 112 is a perspective view of the deployment tool shown
in FIG. 106 engaging the distal portion of the implant shown in
FIG. 100 in the first configuration.
[0102] FIG. 113 is a flow chart illustrating a method of treating a
spinal condition according to an embodiment of the invention.
[0103] FIG. 114 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention disposed between a first spinous process and second
spinous process.
[0104] FIG. 115 is a schematic illustration of a lateral view of
the implant shown in FIG. 114 in the first configuration.
[0105] FIG. 116 is a schematic illustration of a posterior view of
the implant shown in FIG. 114 in a second configuration.
[0106] FIG. 117 is a schematic illustration of a lateral view of
the implant shown in FIG. 114 in the second configuration.
[0107] FIG. 118 is a posterior view of an implant in a first
configuration according to an embodiment of the invention disposed
between a first spinous process and second spinous process.
[0108] FIG. 119 is a cross-sectional posterior view of the implant
shown in FIG. 118 in the first configuration.
[0109] FIG. 120 is a cross-sectional of the implant shown in FIG.
118 in the first configuration taken along line A-A.
[0110] FIG. 121 is a posterior view of the implant shown in FIG.
118 in the second configuration.
[0111] FIG. 122 is a cross-sectional posterior view of the implant
shown in FIG. 118 in the second configuration.
[0112] FIG. 123 is a cross-sectional of the implant shown in FIG.
105 in the second configuration taken along line A-A.
[0113] FIG. 124 is a posterior view of an implant in a first
configuration according to an embodiment of the invention disposed
between a first spinous process and second spinous process.
[0114] FIG. 125 is a lateral view of the implant shown in FIG. 111
in the first configuration.
[0115] FIG. 126 is a posterior view of the implant shown in FIG.
111 in a second configuration.
[0116] FIG. 127 is a lateral view of the implant shown in FIG. 111
in the second configuration.
[0117] FIG. 128 is a posterior view of an implant in a first
configuration according to an embodiment of the invention disposed
between a first spinous process and second spinous process.
[0118] FIG. 129 is a posterior view of the implant shown in FIG.
115 in a second configuration.
[0119] FIG. 130 is a flow chart illustrating a method according to
an embodiment of the invention.
[0120] FIG. 131 is a flow chart illustrating a method according to
an embodiment of the invention.
[0121] FIG. 132 is a schematic illustration of an embodiment of a
medical device shown within a schematic representation of a
body.
[0122] FIG. 133 is an exploded side view of a medical device
according to an embodiment of the invention.
[0123] FIG. 134 is a distal end view of the implant shown in FIG.
133 taken along line 134-134 in FIG. 133.
[0124] FIG. 135 is a cross-sectional view of the insertion tool
shown in FIG. 133 taken along line 135-135 in FIG. 133.
[0125] FIG. 136 is a top view of a portion of the medical device of
FIG. 133 shown partially disposed within a body in a first
position.
[0126] FIG. 137 is a top view of a portion of the medical device of
FIG. 133 shown partially disposed within a body in a second
position.
[0127] FIG. 138 is a top view of a portion of a medical device
according to an embodiment of the inventions shown partially
disposed within a body.
[0128] FIG. 139 is an exploded side view of a medical device
according to another embodiment of the invention.
[0129] FIG. 140 is a distal end view of the implant shown in FIG.
139.
[0130] FIG. 141 is a distal end view of the implant shown in FIG.
139 illustrating a portion of the guide member of FIG. 139 disposed
within a distal end portion of the implant.
[0131] FIG. 142 is a side exploded view of a medical device
according to another embodiment of the invention.
[0132] FIG. 143 is a top view of the medical device of FIG. 142 and
an insertion tool shown partially disposed within a body.
[0133] FIG. 144 is a flowchart of a method according to an
embodiment of the invention.
[0134] FIG. 145 is a side view of a measurement device according to
an embodiment of the invention.
[0135] FIG. 146 is a side view of the measurement device of FIG.
145 shown partially disposed within a body and illustrating a first
position and a second position of the measurement device.
[0136] FIG. 147 is a side perspective view of a measurement device
according to another embodiment of the invention.
[0137] FIG. 148 is a side view of the measurement device of FIG.
147 shown adjacent to an image of a portion of a spine.
[0138] FIG. 149 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention.
[0139] FIG. 150 is a schematic illustration of a posterior view of
the implant shown in FIG. 149 in a second configuration disposed
between a first spinous process and second spinous process.
[0140] FIG. 151 is a schematic illustration of a posterior view of
the implant shown in FIG. 149 in a third configuration.
[0141] FIG. 152 is a schematic illustration of a posterior view of
the implant shown in FIG. 149 in a fourth configuration.
[0142] FIG. 153 is a schematic illustration of a posterior view of
an implant in a first configuration according to an embodiment of
the invention.
[0143] FIG. 154 is a schematic illustration of a posterior view of
the implant shown in FIG. 153 in a second configuration disposed
between a first spinous process and second spinous process.
[0144] FIG. 155 is a schematic illustration of a posterior view of
the implant shown in FIG. 153 in a third configuration.
[0145] FIG. 156 is a schematic illustration of a posterior view of
the implant shown in FIG. 153 in a fourth configuration.
[0146] FIG. 157 is a flow chart illustrating a method of treating a
spinal condition according to an embodiment of the invention.
[0147] FIG. 158 is a flow chart illustrating a method of treating a
spinal condition according to an embodiment of the invention.
DETAILED DESCRIPTION
[0148] As used in this specification and the appended claims, the
singular forms "a," "an" and "the" include plural referents unless
the context clearly dictates otherwise. Thus, for example, the term
"a member" is intended to mean a single member or a combination of
members, "a material" is intended to mean one or more materials, or
a combination thereof. Furthermore, the words "proximal" and
"distal" refer to direction closer to and away from, respectively,
an operator (e.g., surgeon, physician, nurse, technician, etc.) who
would insert the medical device into the patient, with the tip-end
(i.e., distal end) of the device inserted inside a patient's body
first. Thus, for example, the implant end first inserted inside the
patient's body would be the distal end of the implant, while the
implant end to last enter the patient's body would be the proximal
end of the implant.
[0149] In some embodiments, an apparatus includes a support member
and a retention member. The support member has at least a portion
configured to be disposed between a first spinous process and a
second spinous process. The retention member is movably coupled to
an end portion of the support member. The retention member is
configured to displace a bodily tissue. The retention member is
configured to move relative to the support member from a first
position to a second position. The retention member is configured
to limit movement of the support member along a longitudinal axis
of the support member and relative to the first spinous process and
the second spinous process when in the second position. In some
embodiments, for example, the retention member and a portion of the
support member collectively form a portion of a saddle configured
to receive a portion of the first spinous process when the
retention member is in the second position.
[0150] In some embodiments, an apparatus includes a first member
and a second member. The first member has a longitudinal axis, a
first surface, and a second surface offset from the longitudinal
axis by a non-zero angle. At least a portion of the first surface
is configured to engage a spinous process. The second member is
rotatably coupled to a distal end of the first member. The second
member is configured to move relative to the first member between a
first position and a second position. In some embodiments, for
example, the second member is configured to rotate relative to the
first member about an axis substantially parallel to the
longitudinal axis of the first member. When the second member is in
the first position, at least a portion of a surface of the second
member is disposed adjacent at least a portion of the second
surface of the first member. In some embodiments, for example, the
surface of the second member is in contact with the portion of the
second surface of the first member when the second member is in the
first position. When the second member is in the second position,
the portion of the second surface of the second member is spaced
apart from the portion of the second surface of the first member.
The portion of the surface of the second member is configured to
limit movement of the first member along the longitudinal axis and
relative to the spinous process when the second member is in the
second position.
[0151] In some embodiments, an apparatus includes a support member
and a retention member rotatably coupled to the distal end of the
support member. The support member has at least a portion
configured to engage adjacent spinous processes. A distal end of
the support member has a cross-sectional area normal to a
longitudinal axis of the support member. The retention member has a
cross-sectional area normal to the longitudinal axis of the support
member. The retention member is configured to rotate relative to
the support member about an axis substantially parallel to the
longitudinal axis of the support member from a first position to a
second position. When the retention member is in the second
position, the retention member is configured to limit movement of
the support member along the longitudinal axis and relative to the
first spinous process and the second spinous process. When the
retention member is in the first position, the cross-sectional area
of the retention member is within the cross-sectional area of the
distal end of the support member when projected on a plane
substantially normal to the longitudinal axis. When the retention
member is in the second position, a portion of the cross-sectional
area of the retention member is outside of the cross-sectional area
of the distal end of the support member when projected on the plane
substantially normal to the longitudinal axis.
[0152] In some embodiments, an apparatus includes a support member
and a retention member movably coupled to the distal end of the
support member. The support member has at least a portion
configured to engage adjacent spinous processes. A distal end of
the support member has a first dimension along a first axis
substantially normal to a longitudinal axis of the support member
and a second dimension along a second axis that is normal to both
the longitudinal axis and the first axis. The second dimension is
greater than the first dimension (e.g., the distal end of the
support member is rectangular). The retention member has a first
dimension along the first axis and a second dimension along the
second axis. The first dimension of the retention member is greater
than the second dimension of the support member and is no greater
than the first dimension of the support member. The second
dimension of the retention member is no greater than the second
dimension of the support member. The retention member is configured
to displace a bodily tissue. The retention member is configured to
move relative to the support member from a first position to a
second position. In some embodiments, for example, when the
retention member is in the first position, the first dimension of
the retention member is aligned with the first dimension of the
support member. When the retention member is in the second
position, the first dimension of the retention member is aligned
with the second dimension of the support member. In this manner,
the retention member can limit movement of the support member along
a longitudinal axis and relative to the spinous processes.
[0153] In some embodiments, an apparatus includes a support member,
a retention member and a locking member. The support member is
configured to be disposed between a first spinous process and a
second spinous process. The retention member is movably coupled to
a distal end of the support member. The retention member is
configured to move from a first position to a second position to
limit movement of the support member along a longitudinal axis and
relative to the first spinous process and the second spinous
process. The locking member is disposed within the support member
and is configured to engage a first surface of the retention member
when the retention member is in the first position such that the
retention member is maintained in the first position. At least a
portion of the locking member is disposed outside of the support
member and is configured to engage a second surface of the
retention member when the retention member is in the second
position such that the retention member is maintained in the second
position. The second surface is different than the first
surface.
[0154] In some embodiments, a method includes disposing at least a
portion of an implant between adjacent spinous processes. The
implant includes a support member and a retention member movably
coupled to the support member. The retention member is rotated from
a first position to a second position such that the retention
member retains a portion of the implant between the adjacent
spinous processes. In some embodiments, the retention member can be
rotated about an axis substantially parallel to a longitudinal axis
of the support member. The retention member is reversibly locked in
the second position.
[0155] In some embodiments, an apparatus includes a support member,
a first retention member and a second retention member. The support
member has at least a portion configured to be disposed between a
first spinous process and a second spinous process. The first
retention member is movably coupled to a first end portion of the
support member. The second retention member is movably coupled to a
second end portion of the support member. The second retention
member is coupled to the first retention member such that the first
retention member and the second retention member are configured to
collectively move relative to the support member from a first
position to a second position. The first retention member and the
second retention member are configured to limit movement of the
support member relative to the first spinous process and the second
spinous process when in the second position.
[0156] In some embodiments, an apparatus includes a support member
and a retention member rotatably coupled to the support member. The
support member has an outer surface configured to be disposed
between a first spinous process and a second spinous process. The
retention member has a first end portion and a second end portion.
The first end portion of the retention member is spaced apart from
the outer surface of the support member by a first distance along
an axis substantially normal to a longitudinal axis of the support
member when the outer surface of the support member is disposed
between the first spinous process and the second spinous process.
The second end portion of the retention member is spaced apart from
the outer surface of the support member by a second distance along
the axis substantially normal to the longitudinal axis of the
support member when the outer surface of the support member is
disposed between the first spinous process and the second spinous
process. The first end portion of the retention member and the
second end portion of the retention member are configured to
cooperatively limit movement of the support member along the
longitudinal axis of the support member and relative to the first
spinous process and the second spinous process. In some
embodiments, for example, the first end portion of the retention
member is configured to engage the first spinous process when the
outer surface of the support member is disposed between the first
spinous process and the second spinous process. In some
embodiments, for example, the second end portion of the retention
member is configured to engage the second spinous process when the
outer surface of the support member is disposed between the first
spinous process and the second spinous process.
[0157] In some embodiments, an apparatus includes a support member
and a retention member rotatably coupled to the support member
about an axis substantially normal to a longitudinal axis of the
support member. The support member has a portion configured to be
disposed between a first spinous process and a second spinous
process. The retention member has a first end portion, a second end
portion, and a central portion. The central portion of the
retention member is disposed within the support member. The first
end portion of the retention member is disposed outside of a distal
end portion of the support member and is configured to engage the
first spinous process when the portion of the support member is
disposed between the first spinous process and the second spinous
process. The second end portion of the retention member is disposed
outside of a proximal end portion of the support member and is
configured to engage the second spinous process when the portion of
the support member is disposed between the first spinous process
and the second spinous process.
[0158] In some embodiments, an apparatus includes a support member
and a retention member rotatably coupled to the support member
between a first position and a second position. The support member
has a portion configured to be disposed between a first spinous
process and a second spinous process. A distal end portion of the
support member has a cross-sectional area normal to a longitudinal
axis of the support member. The retention member has an end portion
and a central portion. The central portion is disposed within the
support member. The end portion of the retention member is
configured to displace a bodily tissue, such as for example, a
supraspinous ligament. The end portion of the retention member has
a cross-sectional area normal to the longitudinal axis of the
support member. The cross-sectional area of the end portion of the
retention member is within the cross-sectional area of the distal
end portion of the support member when projected on a plane
substantially normal to the longitudinal axis and when the
retention member is in the first position. At least a portion of
the cross-sectional area of the end portion of retention member is
outside of the cross-sectional area of the distal end of the
support member when projected on the plane substantially normal to
the longitudinal axis and when the retention member is in the
second position.
[0159] In some embodiments, an apparatus includes a first elongate
member and a second elongate member rotatably coupled to the first
elongate member. The first elongate member and the second elongate
member collectively have a first configuration and a second
configuration. When the first elongate member and the second
elongate member are in the first configuration, a longitudinal axis
of the second elongate member is substantially parallel to a
longitudinal axis of the first elongate member. When the first
elongate member and the second elongate member are in the second
configuration, the longitudinal axis of the second elongate member
is angularly offset from the longitudinal axis of the first
elongate member. When the first elongate member and the second
elongate member are in the second configuration, a portion of the
first elongate member is configured to contact a first side of a
spinous process and a portion of the second elongate member is
configured to contact a second side of the spinous process opposite
the first side to cooperatively limit movement of the first
elongate member relative to the spinous process.
[0160] In some embodiments, a method includes disposing at least a
portion of an implant between a first spinous process and a second
spinous process. The implant includes a support member and a
retention member rotatably coupled to the support member. The
retention member is rotated relative to the support member from a
first position to a second position such that a first end portion
of the retention member is disposed outside of a proximal end
portion of the support member and a second end portion of the
retention member is disposed outside a distal end portion of the
support member. The first end portion of the retention member and
the second end portion of the retention member cooperatively limit
movement of the support member along a longitudinal axis of the
support member and relative to the first spinous process and the
second spinous process. In some embodiments, the method can
optionally include locking the retention member in the second
position after the rotating.
[0161] In some embodiments, a method includes disposing at least a
portion of an implant between a first spinous process and a second
spinous process. The implant includes a first elongate member and a
second elongate member rotatably coupled to the first elongate
member. The second elongate member is rotated relative to the first
elongate member about an axis substantially normal to a
longitudinal axis of the support member from a first position to a
second position such that a portion of the first elongate member is
engagable with a first surface of the first spinous process and a
portion of the second elongate member is engagable with a second
surface of the first spinous process opposite the first surface to
limit lateral movement of the implant.
[0162] In one variation, a method provides for the insertion of an
implant between adjacent bone structures. For example, an implant
is inserted between adjacent spinous processes. The implant can be
advanced within a body to a location between adjacent bone
structures with an insertion tool and guided by a path defined by a
guide member releasably coupled to the guide member. For example,
the guide member can define a curved path through the body and a
portion of the path goes between the adjacent bone structures.
[0163] In one embodiment, a method includes inserting at least a
portion of a guide member between adjacent spinous processes. An
implant that is coupled to the guide member is advanced such that
the guide member is advanced along a curved path until at least a
portion of the implant is positioned between the adjacent spinous
processes. An apparatus according to an embodiment of the invention
includes an implant configured to be disposed between adjacent
spinous processes and a guide member having a proximal end
releasably couplable to the implant. The implant is stationary
relative to the guide member when the guide member is releasably
coupled to the implant. The guide member has a curved shape and a
distal tip configured to be percutaneously inserted into a
body.
[0164] In another embodiment, a method includes percutaneously
inserting a guide member at a first exterior location of a body. An
implant coupled to a proximal end of the guide member is advanced
along a path defined by the guide member such that during the
advancing, a proximal end of the implant is at a fixed distance
from the proximal end of the guide member. A distal end of the
guide member is advanced through a second exterior location of the
body.
[0165] In another embodiment, an apparatus includes an implant
configured to be inserted into a body and a guide member. The guide
member has a proximal end releasably couplable to the implant such
that a distance between a proximal end of the implant and the
proximal end of the guide member is fixed during insertion of the
implant into the body. The guide member has a distal tip configured
to be percutaneously inserted into the body at a first location and
exit the body at a second location different than the first
location.
[0166] In some embodiments, a method includes inserting an implant
having a support member and a retention member movably coupled to
the support member such that at least a portion of the support
member of the implant is disposed between a first spinous process
and a second spinous process. The implant is rotated relative to
the first spinous process and the second spinous process about an
axis substantially normal to a mid-line axis of a spinal column
while the portion of the support member is disposed between the
first spinous process and the second spinous process. In some
embodiments, the implant is rotated such that an inner surface of
an end portion of the retention member is between an outer surface
of the end portion of the retention member and the first spinous
process. The retention member is translated relative to the support
member.
[0167] In some embodiments, a method includes inserting an implant
having a first member, a second member and a third member such that
at least a portion of the first member of the implant is disposed
between a first spinous process and a second spinous process. The
implant is rotated relative to the first spinous process and the
second spinous process such that an inner surface of the second
member is between an outer surface of the second member and the
first spinous process and an inner surface of the third member is
between an outer surface of the third member and the second spinous
process. The second member is translated relative to the first
member after the implant is rotated. In some embodiments, the third
member is translated relative to the first member after the implant
is rotated.
[0168] In some embodiments, an apparatus includes a support member
and a retention member movably coupled to an end portion of the
support member. The support member is configured to have at least a
portion disposed between a first spinous process and a second
spinous process. The retention member is configured to translate
relative to the support member from a first position to a second
position along a longitudinal axis of the retention member. The
retention member is configured to limit movement of the support
member relative to the first spinous process and the second spinous
process when in the second position.
[0169] In some embodiments, an apparatus includes a support member,
a first retention member and a second retention member. The support
member is configured to have at least a portion disposed between a
first spinous process and a second spinous process. The first
retention member is movably coupled to a first end portion of the
support member. The first retention member is configured to
translate relative to the support member from a first position to a
second position along a longitudinal axis of the first retention
member. The second retention member is movably coupled to a second
end portion of the support member. The second retention member is
configured to translate relative to the support member from a first
position to a second position along a longitudinal axis of the
second retention member. In some embodiments, the support member,
the first retention member and the second retention member are
collectively configured to rotate about an axis normal to a
mid-line axis of a spinal column when the portion of the support
member is disposed between the first spinous process and the second
spinous process, the first retention member is in its first
position and the second retention member is in its first
position.
[0170] The term "body" is used here to mean a mammalian body. For
example, a body can be a patient's body, or a cadaver, or a portion
of a patient's body or a portion of a cadaver.
[0171] The term "parallel" or is used herein to describe a
relationship between two geometric constructions (e.g., two lines,
two planes, a line and a plane, two curved surfaces, a line and a
curved surface or the like) in which the two geometric
constructions are substantially non-intersecting as they extend
substantially to infinity. For example, as used herein, a line is
said to be parallel to a curved surface when the line and the
curved surface do not intersect as they extend to infinity.
Similarly, when a planar surface (i.e., a two-dimensional surface)
is said to be parallel to a line, every point along the line is
spaced apart from the nearest portion of the surface by a
substantially equal distance. Two geometric constructions are
described herein as being "parallel" or "substantially parallel" to
each other when they are nominally parallel to each other, such as
for example, when they are parallel to each other within a
tolerance. Such tolerances can include, for example, manufacturing
tolerances, measurement tolerances or the like.
[0172] The term "normal" is used herein to describe a relationship
between two geometric constructions (e.g., two lines, two planes, a
line and a plane, two curved surfaces, a line and a curved surface
or the like) in which the two geometric constructions intersect at
an angle of approximately 90 degrees within at least one plane. For
example, as used herein, a line is said to be normal to a curved
surface when the line and the curved surface intersect at an angle
of approximately 90 degrees within a plane. Two geometric
constructions are described herein as being "normal" or
"substantially normal" to each other when they are nominally normal
to each other, such as for example, when they are normal to each
other within a tolerance. Such tolerances can include, for example,
manufacturing tolerances, measurement tolerances or the like.
[0173] FIG. 1 is a schematic illustration of a medical device
according to an embodiment of the invention adjacent two adjacent
spinous processes. The medical device 10 includes a proximal
portion 12, a distal portion 14 and a central portion 16. The
medical device 10 has a first configuration in which it can be
inserted between adjacent spinous processes S. The central portion
16 is configured to contact the spinous processes S to prevent
over-extension/compression of the spinous processes S. In some
embodiments, the central portion 16 does not substantially distract
the adjacent spinous processes S. In other embodiments, the central
portion 16 does not distract the adjacent spinous processes S.
[0174] In the first configuration, the proximal portion 12, the
distal portion 14 and the central portion 16 are coaxial (i.e.,
share a common longitudinal axis). In some embodiments, the
proximal portion 12, the distal portion 14 and the central portion
16 define a tube having a constant inner diameter. In other
embodiments, the proximal portion 12, the distal portion 14 and the
central portion 16 define a tube having a constant outer diameter
and/or inner diameter.
[0175] The medical device 10 can be moved from the first
configuration to a second configuration as illustrated in FIG. 2.
In the second configuration, the proximal portion 12 and the distal
portion 14 are positioned to limit lateral movement of the device
10 with respect to the spinous processes S. The proximal portion 12
and the distal portion 14 are configured to engage the spinous
process (i.e., either directly or through surrounding tissue) in
the second configuration. For purposes of clarity, the tissue
surrounding the spinous processes S is not illustrated.
[0176] In some embodiments, the proximal portion 12, the distal
portion 14 and the central portion 16 are monolithically formed. In
other embodiments, one or more of the proximal portion 12, the
distal portion 14 and the central portion 16 are separate
components that can be coupled together to form the medical device
10. For example, the proximal portion 12 and distal portion 14 can
be monolithically formed and the central portion can be a separate
component that is coupled thereto.
[0177] In use, the spinous processes S can be distracted prior to
inserting the medical device 10. Distraction of spinous processes
is discussed below. When the spinous processes are distracted, a
trocar can be used to define an access passage for the medical
device 10. In some embodiments, the trocar can be used to define
the passage as well as distract the spinous processes S. Once an
access passage is defined, the medical device 10 is inserted
percutaneously and advanced between the spinous processes, distal
end 14 first, until the central portion 16 is located between the
spinous processes S. Once the medical device 10 is in place between
the spinous processes, the proximal portion 12 and the distal
portion 14 are moved to the second configuration, either serially
or simultaneously.
[0178] In some embodiments, the medical device 10 is inserted
percutaneously (i.e., through an opening in the skin) and in a
minimally-invasive manner. For example, as discussed in detail
herein, the size of portions of the implant is expanded after the
implant is inserted between the spinous processes. Once expanded,
the size of the expanded portions of the implant is greater than
the size of the opening. For example, the size of the
opening/incision in the skin may be between 3 millimeters in length
and 25 millimeters in length. In some embodiments, the size of the
implant in the expanded configuration is between 3 and 25
millimeters.
[0179] FIG. 3 is a schematic illustration of a deformable element
18 that is representative of the characteristics of, for example,
the distal portion 14 of the medical device 10 in a first
configuration. The deformable member 18 includes cutouts A, B, C
along its length to define weak points that allow the deformable
member 18 to deform in a predetermined manner. Depending upon the
depth d of the cutouts A, B, C and the width w of the throats T1,
T2, T3, the manner in which the deformable member 18 deforms under
an applied load can be controlled and varied. Additionally,
depending upon the length L between the cutouts A, B, C (i.e., the
length of the material between the cutouts) the manner in which the
deformable member 18 deforms can be controlled and varied.
[0180] FIG. 4 is a schematic illustration of the expansion
properties of the deformable member 18 illustrated in FIG. 3. When
a load is applied, for example, in the direction indicated by arrow
X, the deformable member 18 deforms in a predetermined manner based
on the characteristics of the deformable member 18 as described
above. As illustrated in FIG. 4, the deformable member 18 deforms
most at cutouts B and C due to the configuration of the cutout C
and the short distance between cutouts B and C. In some
embodiments, the length of the deformable member 18 between cutouts
B and C is sized to fit adjacent a spinous process.
[0181] The deformable member 18 is stiffer at cutout A due to the
shallow depth of cutout A. As indicated in FIG. 4, a smooth
transition is defined by the deformable member 18 between cutouts A
and B. Such a smooth transition causes less stress on the tissue
surrounding a spinous process than a more drastic transition such
as between cutouts B and C. The dimensions and configuration of the
deformable member 18 can also determine the timing of the
deformation at the various cutouts. The weaker (i.e., deeper and
wider) cutouts deform before the stronger (i.e., shallower and
narrower) cutouts.
[0182] FIGS. 5 and 6 illustrate a spinal implant 100 in a first
configuration and second configuration, respectively. As shown in
FIG. 5, the spinal implant 100 is collapsed in a first
configuration and can be inserted between adjacent spinous
processes. The spinal implant 100 has a first expandable portion
110, a second expandable portion 120 and a central portion 150. The
first expandable portion 110 has a first end 112 and a second end
1140. The second expandable portion 120 has a first end 122 and a
second end 124. The central portion 150 is coupled between second
end 1140 and first end 122. In some embodiment, the spinal implant
100 is monolithically formed.
[0183] The first expandable portion 110, the second expandable
portion 120 and the central portion 150 have a common longitudinal
axis A along the length of spinal implant 100. The central portion
150 can have the same inner diameter as first expandable portion
110 and the second expandable portion 120. In some embodiments, the
outer diameter of the central portion 150 is smaller than the outer
diameter of the first expandable portion 110 and the second
expandable portion 120.
[0184] In use, spinal implant 100 is inserted percutaneously
between adjacent spinous processes. The first expandable portion
110 is inserted first and is moved past the spinous processes until
the central portion 150 is positioned between the spinous
processes. The outer diameter of the central portion 150 can be
slightly smaller than the space between the spinous processes to
account for surrounding ligaments and tissue. In some embodiments,
the central portion directly contacts the spinous processes between
which it is positioned. In some embodiments, the central portion of
spinal implant 100 is a fixed size and is not compressible or
expandable.
[0185] The first expandable portion 110 includes expanding members
115, 117 and 119. Between the expanding members 115, 117, 119,
openings 111 are defined. As discussed above, the size and shape of
the openings 111 influence the manner in which the expanding
members 115, 117, 119 deform when an axial load is applied. The
second expandable portion 120 includes expanding members 125, 127
and 129. Between the expanding members 125, 127, 129, openings 121
are defined. As discussed above, the size and shape of the openings
121 influence the manner in which the expanding members 125, 127,
129 deform when an axial load is applied.
[0186] When an axial load is applied to the spinal implant 100, the
spinal implant 100 expands to a second configuration as illustrated
in FIG. 6. In the second configuration, first end 112 and second
end 1140 of the first expandable portion 110 move towards each
other and expanding members 115, 117, 119 project substantially
laterally away from the longitudinal axis A. Likewise, first end
122 and second end 124 of the second expandable portion 120 move
towards one another and expanding members 125, 127, 129 project
laterally away from the longitudinal axis A. The expanding members
115, 117, 119, 125, 127, 129 in the second configuration form
projections that extend to positions adjacent to the spinous
processes between which the spinal implant 100 is inserted. In the
second configuration, the expanding members 115, 117, 119, 125,
127, 129 inhibit lateral movement of the spinal implant 100, while
the central portion 150 prevents the adjacent spinous processes
from moving together any closer than the distance defined by the
diameter of the central portion 150.
[0187] A spinal implant 200 according to an embodiment of the
invention is illustrated in FIGS. 7-9 in various configurations.
Spinal implant 200 is illustrated in a completely collapsed
configuration in FIG. 7 and can be inserted between adjacent
spinous processes. The spinal implant 200 has a first expandable
portion 210, a second expandable portion 220 and a central portion
250. The first expandable portion 210 has a first end 212 and a
second end 214. The second expandable portion 220 has a first end
222 and a second end 224. The central portion 250 is coupled
between second end 214 and first end 222.
[0188] The first expandable portion 210, the second expandable
portion 220 and the central portion 250 have a common longitudinal
axis A along the length of spinal implant 200. The central portion
250 can have the same inner diameter as first expandable portion
210 and the second expandable portion 220. The outer diameter of
the central portion 250 is greater than the outer diameter of the
first expandable portion 210 and the second expandable portion 220.
The central portion 250 can be monolithically formed with the first
expandable portion 210 and the second expandable portion 220 or can
be a separately formed sleeve coupled thereto or thereupon.
[0189] In use, spinal implant 200 is inserted percutaneously
between adjacent spinous processes S. The first expandable portion
210 is inserted first and is moved past the spinous processes S
until the central portion 250 is positioned between the spinous
processes S. The outer diameter of the central portion 250 can be
slightly smaller than the space between the spinous processes S to
account for surrounding ligaments and tissue. In some embodiments,
the central portion 250 directly contacts the spinous processes S
between which it is positioned. In some embodiments, the central
portion 250 of spinal implant 200 is a fixed size and is not
compressible or expandable. In other embodiments, the central
portion 250 can compress to conform to the shape of the spinous
processes.
[0190] The first expandable portion 210 includes expanding members
215, 217 and 219. Between the expanding members 215, 217, 219,
openings 211 are defined. As discussed above, the size and shape of
the openings 211 influence the manner in which the expanding
members 215, 217, 219 deform when an axial load is applied. Each
expanding member 215, 217, 219 of the first expandable portion 210
includes a tab 213 extending into the opening 211 and an opposing
mating slot 218. In some embodiments, the first end 212 of the
first expandable portion 210 is rounded to facilitate insertion of
the spinal implant 200.
[0191] The second expandable portion 220 includes expanding members
225, 227 and 229. Between the expanding members 225, 227, 229,
openings 221 are defined. As discussed above, the size and shape of
the openings 221 influence the manner in which the expanding
members 225, 227, 229 deform when an axial load is applied. Each
expanding member 225, 227, 229 of the second expandable portion 220
includes a tab 223 extending into the opening 221 and an opposing
mating slot 228.
[0192] When an axial load is applied to the spinal implant 200, the
spinal implant moves to a partially expanded configuration as
illustrated in FIG. 8. In the partially expanded configuration,
first end 222 and second end 224 of the second expandable portion
220 move towards one another and expanding members 225, 227, 229
project laterally away from the longitudinal axis A. To prevent the
second expandable portion 220 from over-expanding, the tab 223
engages slot 228 and acts as a positive stop. As the axial load
continues to be imparted to the spinal implant 200 after the tab
223 engages slot 228, the load is transferred to the first
expandable portion 210. Accordingly, the first end 212 and the
second end 214 then move towards one another until tab 213 engages
slot 218 in the fully expanded configuration illustrated in FIG. 9.
In the second configuration, expanding members 215, 217, 219
project laterally away from the longitudinal axis A. In some
alternative embodiments, the first expandable portion and the
second expandable portion expand simultaneously under an axial
load.
[0193] The order of expansion of the spinal implant 200 can be
controlled by varying the size of openings 211 and 221. For
example, in the embodiments shown in FIGS. 7-9, the opening 221 is
slightly larger than the opening 211. Accordingly, the notches 226
are slightly larger than the notches 216. As discussed above with
respect to FIGS. 3 and 4, for this reason, the second expandable
portion 220 will expand before the first expandable portion 210
under an axial load.
[0194] In the second configuration, the expanding members 215, 217,
219, 225, 227, 229 form projections that extend adjacent the
spinous processes S. Once in the second configuration, the
expanding members 215, 217, 219, 225, 227, 229 inhibit lateral
movement of the spinal implant 200, while the central portion 250
prevents the adjacent spinous processes from moving together any
closer than the distance defined by the diameter of the central
portion 250.
[0195] The portion P of each of the expanding members 215, 217,
219, 225, 227, 229 proximal to the spinous process S expands such
that portion P is substantially parallel to the spinous process S.
The portion D of each of the expanding members 215, 217, 219, 225,
227, 229 distal from the spinous process S is angled such that less
tension is imparted to the surrounding tissue.
[0196] In the second configuration, the expanding members 225, 227,
229 are separate by approximately 120 degrees from an axial view as
illustrated in FIG. 10. While three expanding members are
illustrated, two or more expanding members may be used and arranged
in an overlapping or interleaved fashion when multiple implants 200
are inserted between multiple adjacent spinous processes.
Additionally, regardless of the number of expanding members
provided, the adjacent expanding members need not be separated by
equal angles or distances.
[0197] The spinal implant 200 is deformed by a compressive force
imparted substantially along the longitudinal axis A of the spinal
implant 200. The compressive force is imparted, for example, by
attaching a rod (not illustrated) to the first end 212 of the first
expandable portion 210 and drawing the rod along the longitudinal
axis while imparting an opposing force against the second end 224
of the second expandable portion 220. The opposing forces result in
a compressive force causing the spinal implant 200 to expand as
discussed above.
[0198] The rod used to impart compressive force to the spinal
implant 200 can be removably coupled to the spinal implant 200. For
example, the spinal implant 200 can include threads 208 at the
first end 212 of the first expandable portion 210. The force
opposing that imparted by the rod can be applied by using a push
bar (not illustrated) that is removably coupled to the second end
224 of the second expandable portion 220. The push rod can be
aligned with the spinal implant 200 by an alignment notch 206 at
the second end 224. The spinal implant 200 can also be deformed in
a variety of other ways, using a variety of expansion devices (also
referred to herein as insertion tools, deployment tools and/or
removal tools). While various types of implants are illustrated
with various types of expansion devices, the expansion devices
described herein can be used with any of the implants described
herein.
[0199] FIGS. 11-16 illustrate an expansion device 1500 (also
referred to herein as an insertion tool or a deployment tool)
according to an embodiment of the invention. Although no particular
implant is illustrated in FIGS. 11-16, any of the implants
described herein, such as, for example, implant 200 (see FIG. 7),
can be used with the expansion device 1500. The expansion device
1500 includes a guide handle 1510, a knob assembly 1515, a shaft
1520, a rod 1570 and an implant support portion 1530. The expansion
device 1500 is used to insert an implant (not illustrated) in
between adjacent spinous processes and expand the implant such that
it is maintained in position between the spinous processes as
described above. Both the guide handle 1510 and the knob assembly
1515 can be grasped to manipulate the expansion device 1500 to
insert the implant. As described in more detail herein, the knob
assembly 1515 is configured such that as the knob assembly 1515 is
actuated, the rod 1570 translates and/or rotates within the shaft
1520; when the rod 1570 translates, the implant (not illustrated)
is moved between its collapsed configuration and its expanded
configuration; when the rod 1570 rotates, the implant is disengaged
from the rod 1570.
[0200] As best illustrated in FIGS. 15 and 16, the implant support
portion 1530 includes a receiving member 1538 and a spacer 1532.
The receiving member 1538 includes a side wall 1540 that is coupled
to and supported by the distal end of the shaft 1520. The side wall
1540 defines an alignment protrusion 1536 and a receiving area 1542
configured to receive a portion of the spacer 1532. The implant
slides over spacer 1532 until its proximal end is received within a
recess 1534 defined by the side wall 1540 and the outer surface of
the spacer 1532. The alignment protrusion 1536 is configured to
mate with a corresponding notch on the implant (see, e.g.,
alignment notch 206 in FIG. 7) to align the implant with respect to
the expansion device. Once the implant is aligned within the
implant support portion 1530, the distal end of the implant is
threadedly coupled to the distal end of rod 1570.
[0201] As illustrated, the spacer 1532 ensures that the implant is
aligned longitudinally during the insertion and expansion process.
The spacer 1532 can also be configured to maintain the shape of the
implant during insertion and to prevent the expandable portions of
the implant from extending inwardly during deployment of the
implant. For example, in some embodiments, the spacer 1532 can be
constructed from a solid, substantially rigid material, such as
stainless steel, having an outer diameter and length corresponding
to the inner diameter and length of the implant. In other
embodiments, the expansion device can be configured to be used with
implants that include an inner core configured to provide
structural support to the implant (see, for example, FIGS. 17-23).
In such embodiments, as described in more detail herein, the spacer
of the insertion tool can be configured to cooperate with the inner
core of the implant to provide the alignment and structural support
of the implant during insertion and expansion.
[0202] The knob assembly 1515 includes an upper housing 1517 that
threadedly receives the shaft 1520, an actuator knob 1550 and a
release knob 1560 as best illustrated in FIG. 14. Upper housing
1517 includes internal threads 1519 that mate with external threads
1521 on shaft 1520. The proximal end of rod 1570 is coupled to the
knob assembly 1515 by an adapter 1554, which is supported by two
thrust bearings 1552. Actuator knob 1550 is coupled to the upper
housing 1517 and is engaged with the adapter 1554 such that when
actuator knob 1550 is turned in the direction indicated by arrows E
(see FIG. 13), the rod 1570 translates axially relative to the
shaft 1520 towards the proximal end of the device 1500, thereby
acting as a draw bar and opposing the movement of the implant in
the distal direction. In other words, when the implant is inserted
between adjacent spinous processes and the actuator knob 1515 is
turned, the distal end of the implant support portion 1530 imparts
an axial force against the proximal end of the implant, while the
rod 1570 causes an opposing force in the proximal direction. In
this manner, the forces imparted by the implant support portion and
the rod 1570 cause portions of the implant to expand in a
transverse configuration such that the implant is maintained in
position between the spinous processes as described above. The
expansion device 1500 can also be used to move the implant from its
expanded configuration to its collapsed configuration by turning
the actuator knob 1550 in the opposite direction.
[0203] Once the implant is in position and fully expanded, the
release knob 1560 is turned in the direction indicated by arrow R
(see FIG. 13) thereby causing the rod 1570 to rotate within the
shaft 1520. In this manner, the implant can be disengaged from the
rod 1570. During this operation, the implant is prevented from
rotating by the alignment protrusion 1536, which is configured to
mate with a corresponding notch on the implant. Once the implant is
decoupled from the rod 1570, the expansion tool 1500 can then be
removed from the patient.
[0204] Although the knob assembly 1515 is shown and described as
including an actuator knob 1550 and a release knob 1560 that are
coaxially arranged with a portion of the release knob 1560 being
disposed within the actuator knob 1550, in some embodiments, the
release knob is disposed apart from the actuator knob. In other
embodiments, the release knob and the actuator knob are not
coaxially located. In yet other embodiments, the knob assembly 1515
does not include knobs having a circular shape, but rather includes
levers, handles or any other device suitable for actuating the rod
relative to the shaft as described above.
[0205] FIGS. 17-23 illustrate an implant 6610 according to another
embodiment of the invention. The implant 6610 can be moved between
a collapsed configuration, as shown in FIGS. 17 and 18, and an
expanded configuration, as shown in FIGS. 19-23. The implant 6610
includes an outer shell 6670 having a distal portion 6612, a
proximal portion 6614, and a central portion 6616. The outer shell
6670 defines a series of openings 6618 disposed between the distal
portion 6612 and the central portion 6616, and the proximal portion
6614 and the central portion 6616. The outer shell 6670 includes a
series of tabs 6620, a pair of which are disposed opposite each
other, along the longitudinal axis of the implant 6610, on either
side of each opening 6618. The outer shell 6670 also includes
expandable portions 6640, which form extensions 6642 that extend
radially from the outer shell 6670 when the implant 6610 is in the
expanded configuration. As illustrated best in FIGS. 19-23, the
arrangement of the openings 6618 and the tabs 6620 effect the shape
and/or size of the extensions 6642. In some embodiments, the
opposing tabs 6620 can be configured to engage each other when the
implant 6610 is in the expanded configuration, thereby serving as a
positive stop to limit the amount of expansion. In other
embodiments, for example, the opposing tabs 6620 can be configured
to engage each other during the expansion process, thereby serving
as a positive stop, but remain spaced apart when the implant 6610
is in the expanded configuration (see, for example, FIGS. 19-23).
In such embodiments, the elastic properties of the extensions 6642
can cause a slight "spring back," thereby causing the opposing tabs
6620 to be slightly spaced apart when the expansion device (also
referred to as an insertion tool or a deployment tool) is
disengaged from the implant 6610.
[0206] As illustrated best in FIG. 17, when the implant is in the
collapsed configuration, the expandable portions 6640 are contoured
to extend slightly radially from remaining portions of the outer
shell 6670. In this manner, the expandable portions 6640 are biased
such that when a compressive force is applied, the expandable
portions 6640 will extend outwardly from the outer shell 6670. The
expandable portions 6640 can be biased using any suitable
mechanism. In some embodiments, for example, the expandable
portions can be biased by including a notch in one or more
locations along the expandable portion, as previously described. In
other embodiments, the expandable portions can be biased by varying
the thickness of the expandable portions in an axial direction. In
yet other embodiments, the expandable portions can be stressed or
bent prior to insertion such that the expandable portions are
predisposed to extend outwardly when a compressive force is applied
to the implant. In such embodiments, the radius of the expandable
portions is greater than that of the remaining portions of the
implant (e.g., the remaining cylindrical portions of the
implant).
[0207] The implant 6610 also includes an inner core 6672 disposed
within a lumen 6658 defined by the outer shell 6670. The inner core
6672 is configured to maintain the shape of the implant 6610 during
insertion, to prevent the expandable portions from extending
inwardly into a region inside of the outer shell 6670 during
deployment and/or to maintain the shape of the central portion 6616
once the implant is in its desired position. As such, the inner
core 6670 can be constructed to provide increased compressive
strength to the outer shell 6670. In other words, the inner core
6672 can provide additional structural support to outer shell 6670
(e.g., in a direction transverse to the axial direction) by filling
at least a portion of the region inside outer shell 6670 (e.g.,
lumen 6658) and contacting the walls of outer shell 6670. This can
increase the amount of compressive force that can be applied to the
implant 6610 while the implant 6610 still maintains its shape and,
for example, the desired spacing between adjacent spinous
processes. In some embodiments, the inner core 6672 can define a
lumen 6673, while in other embodiments, the inner core 6672 can
have a substantially solid construction. As illustrated, the inner
core 6672 is fixedly coupled to the outer shell 6670 with a
coupling portion 6674, which is configured to be threadedly coupled
to the distal portion 6612 of the outer shell 6670. The distal end
of the coupling portion 6674 of the inner core 6672 includes an
opening 6675 configured to receive a tool configured to deform the
distal end of the coupling portion 6674. In this manner once the
inner core 6672 is threadedly coupled to the outer shell 6670, the
coupling portion 6674 can be deformed or peened to ensure that the
inner core 6672 does not become inadvertently decoupled from the
outer shell 6670. In some embodiments, an adhesive, such as a
thread-locking compound can be applied to the threaded portion of
the coupling portion 6674 to ensure the that the inner core 6672
does not inadvertently become decoupled from the outer shell 6670.
Although illustrated as being threadedly coupled, the inner core
6672 can be coupled to the outer shell 6670 by any suitable means.
In some embodiments, for example, the inner core 6672 can be
coupled to the central portion 6616 of the outer shell 6670 by, for
example, a friction fit. In other embodiments, the inner core 6672
can be coupled to the outer shell 6670 by an adhesive. The inner
core 6672 can have a length such that the inner core 6672 is
disposed within the lumen 6658 along substantially the entire
length of the outer shell 6670 or only a portion of the length of
the outer shell 6670.
[0208] The proximal portion of the inner core 6672 includes an
opening 6673 configured to receive a portion of an expansion device
7500 (also referred to as an insertion tool or a deployment tool),
as shown in FIGS. 24-31. The expansion device 7500 is similar to
the expansion device 1500 shown and described above (see e.g. FIGS.
11-16). The expansion device 7500 differs, however, from expansion
device 1500 in that the expansion device 7500 includes spacer 7532
configured to cooperate with the inner core 6672 of the implant
6610. In such an arrangement, the threaded portion of rod 7570 of
the expansion device 7500 removably engages to the internal threads
6676 of the inner core 6672 of the implant 6610, rather than
coupling directly to the distal portion of the implant (as shown in
FIGS. 15 and 16). Although the inner core 6672 is shown as being
threadedly coupled to the expansion device 7500, the inner core
6672 can be removably coupled to the expansion device 7500 by any
suitable means, such as a protrusion and detent arrangement.
[0209] In use, once the implant 6610 is positioned on the implant
support portion 7530 of the expansion tool 7500 (see FIGS. 24 and
25), the implant is inserted into the patient's body and disposed
between adjacent spinous processes. Once disposed between adjacent
spinous processes, the expansion device can be used to move the
inner core 6672 axially towards the proximal portion 6614 of the
implant 6610 while simultaneously maintaining the position of the
proximal portion 6614 of the implant 6610, as shown in FIGS. 29 and
31. In this manner, a compressive force is applied along the
longitudinal axis of the outer shell 6670, thereby causing the
outer shell 6670 to fold or bend to form extensions 6642 as
described above. As illustrated, a portion of the spacer 7532 is
received within the receiving area 7542 of the support portion 7530
as the implant 6610 is placed in the expanded configuration.
Similarly, to move the implant 6610 from the expanded configuration
to the collapsed configuration, the expansion device is actuated in
the opposite direction to impart an axial force on the distal
portion 6612 of the outer shell 6610 in a distal direction, moving
the distal portion 6612 distally, and moving the implant 6610 to
the collapsed configuration.
[0210] Once the implant 6610 is in its expanded configuration (see
FIGS. 28-31), the implant 6610 can be disengaged from the expansion
device 7500 by disengaging the distal portion of the rod 7570 from
the opening 6673. The rod 7570 can be disengaged by actuating the
knob assembly 7515 rotate the rod 7570 relative to the shaft 7520,
as discussed above.
[0211] Although shown and described above without reference to any
specific dimensions, in some embodiments, the outer shell 6670 can
have a cylindrical shape having a length of approximately 34.5 mm
(1.36 inches) and a diameter between 8.1 and 14.0 mm (0.32 and 0.55
inches). In some embodiments, the wall thickness of the outer shell
can be approximately 5.1 mm (0.2 inches).
[0212] Similarly, in some embodiments, the inner core 6672 can have
a cylindrical shape having an overall length of approximately 27.2
mm (1.11 inches) and a diameter between 8.1 and 14.0 mm (0.32 and
0.55 inches).
[0213] In some embodiments, the shape and size of the openings 6618
located adjacent the distal portion 6612 can be the same as that
for the openings 6618 located adjacent the proximal portion 6614.
In other embodiments, the openings 6618 can have different sizes
and/or shapes. In some embodiments, the openings 6618 can have a
length of approximately 11.4 mm (0.45 inches) and a width between
4.6 and 10 mm (0.18 and 0.40 inches).
[0214] Similarly, the shape and size of the tabs 6620 can be
uniform or different as circumstances dictate. In some embodiments,
for example, the longitudinal length of the tabs 6620 located
adjacent the proximal portion 6614 can be shorter than the
longitudinal length of the tabs 6620 located adjacent the distal
portion 6612. In this manner, as the implant is moved from the
collapsed configuration to the expanded configuration, the tabs
adjacent the distal portion will engage each other first, thereby
limiting the expansion of the expandable portions 6640 adjacent the
distal portion 6612 to a greater degree than the expandable
portions 6642 located adjacent the proximal portion 6614. In other
embodiments, the longitudinal length of the tabs can be the same.
In some embodiments, the longitudinal length of the tabs can be
between 1.8 and 2.8 mm (0.07 and 0.11 inches). In some embodiments,
the end portions of opposing tabs 6620 can have mating shapes, such
as mating radii of curvature, such that the opposing tabs 6620
engage each other in a predefined manner.
[0215] Although illustrated as having a generally rectangular
shape, the expandable portions 6640 and the resulting extensions
6642 can be of any suitable shape and size. In some embodiments,
for example, the expandable portions can have a longitudinal length
of approximately 11.4 mm (0.45 inches) and a width between 3.6 and
3.8 mm (0.14 and 0.15 inches). In other embodiments, size and/or
shape of the expandable portions located adjacent the proximal
portion 6614 can be different than the size and/or shape of the
tabs 6620 located adjacent the distal portion 6612. Moreover, as
described above, the expandable portions 6640 can be contoured to
extend slightly radially from the outer shell 6670. In some
embodiments, for example, the expandable portions can have a radius
of curvature of approximately 12.7 mm (0.5 inches) along an axis
normal to the longitudinal axis of the implant.
[0216] In some embodiments, the expandable portions 6640 and the
outer shell 6670 are monolithically formed. In other embodiments,
the expandable portions 6640 and the outer shell 6670 are formed
from separate components having different material properties. For
example, the expandable portions 6640 can be formed from a material
having a greater amount of flexibility, while the outer shell 6670
can be formed from a more rigid material. In this manner, the
expandable portions 6640 can be easily moved from the collapsed
configuration to the expanded configuration, while the outer shell
6670 is sufficiently strong to resist undesirable deformation when
in use.
[0217] In one embodiment, an apparatus includes a first body
coupled to a second body. The first body and the second body
collectively are configured to be releasably coupled to an implant
device configured to be disposed between adjacent spinous
processes. A first engaging portion is coupled to the first body,
and a second engaging portion is coupled to the second body. The
first engaging portion and/or the second engaging portion is
configured to be received within a first opening defined by the
implant device. The first body configured to be moved relative to
the second body such that a distance between the first engaging
portion and the second engaging portion is moved between a first
distance and a second distance, and simultaneously a length of the
implant device is moved between a first length and a second
length.
[0218] In another embodiment, a kit includes an implant that is
reconfigurable between an expanded configuration and a collapsed
configuration while disposed between adjacent spinous processes.
The implant has a longitudinal axis and defines an opening. A
deployment tool is configured to be releasably coupled to the
implant. The deployment tool includes an engaging portion
configured to be removably received within the opening of the
implant and extend in a transverse direction relative to the
longitudinal axis when the deployment tool is coupled to the
implant. The deployment tool is configured to move the implant
between the collapsed configuration and the expanded configuration
while the implant is disposed between the adjacent spinous
processes.
[0219] FIGS. 32-35 are schematic illustrations of a posterior view
of a medical device 4000 according to an embodiment of the
invention positioned adjacent two adjacent spinous processes S in a
first configuration (FIG. 32), a second configuration (FIGS. 33 and
35) and a third configuration (FIG. 34). The medical device 4000
includes an expandable member 4002 having an inner area (not shown)
and an outer surface 4010. The outer surface 4010 is configured to
be disposed between the spinous processes S to prevent
over-extension/compression of the spinous processes S. In some
embodiments, the expandable member 4002 distracts the adjacent
spinous processes S. In other embodiments, the expandable member
4002 does not distract the adjacent spinous processes S.
[0220] The expandable member 4002 has a first configuration, a
second configuration and a third configuration. When in each
configuration, the expandable member 4002 has an associated volume.
As illustrated in FIG. 32, the first configuration represents a
substantially contracted condition in which the expandable member
4002 has a minimal volume. When the expandable member 4002 is in
the first configuration, the medical device 4000 is inserted
between the adjacent spinous processes S. As illustrated in FIGS.
33 and 35, the second configuration represents an expanded
condition in which the expandable member 4002 has a large volume.
When the expandable member 4002 is in the second configuration, the
outer surface 4010 of the medical device 4000 contacts the adjacent
spinous processes S during at least a portion of the range of
motion of the spinous processes. As illustrated in FIG. 34, the
third configuration represents a partially expanded condition in
which the expandable member 4002 has a volume between that
associated with the first configuration and that associated with
the second configuration. When the expandable member 4002 is in the
third configuration, the medical device 4000 can be repositioned
between the adjacent spinous processes, as indicated by the arrow
in FIG. 34. The medical device can then be subsequently re-expanded
into the second configuration, as illustrated in FIG. 35.
[0221] FIGS. 36-38 are schematic illustrations of a posterior view
of the medical device 4000 positioned adjacent two adjacent spinous
processes S in a first configuration, a second configuration and a
third configuration, respectively. As described above, when the
expandable member 4002 is in the first configuration, the medical
device 4000 is inserted between the adjacent spinous processes S.
The expandable member 4002 is then expanded to the second
configuration, in which the outer surface 4010 of the medical
device 4000 is disposed between the adjacent spinous processes S.
The expandable member 4002 is then contracted to the third
configuration to facilitate removal of the medical device 4000, as
shown in FIG. 38. In some embodiments, the third configuration can
be the same as the first configuration.
[0222] In use, the adjacent spinous processes S can be distracted
prior to inserting the medical device 4000 into a body, as
described herein. When the spinous processes S are distracted, a
trocar (not shown) can be used to define an access passageway (not
shown) for the medical device 4000. In some embodiments, the trocar
can be used to define the passage as well as to distract the
spinous processes S. Once an access passageway is defined, the
medical device 4000 is inserted percutaneously and advanced between
the spinous processes S and placed in the desired position between
the adjacent spinous processes S. Once the medical device 4000 is
in the desired position, the expandable member is expanded to the
second condition, causing the outer surface 4010 to engage the
spinous processes S.
[0223] In some embodiments, the adjacent spinous processes can be
distracted by a first expandable member (not shown) configured to
distract bone. Upon distraction, the first expandable member is
contracted and removed from the body. The medical device 4000 is
then inserted percutaneously, advanced between the spinous
processes S, placed in the desired position and expanded, as
described above.
[0224] In some embodiments, the medical device 4000 is inserted
percutaneously (i.e., through an opening in the skin) and in a
minimally-invasive manner. For example, as discussed in detail
herein, the overall sizes of portions of the medical device 4000
are increased by transitioning the expandable member 4002 from the
first configuration to the second configuration after the medical
device 4000 is inserted between the adjacent spinous processes S.
When in the expanded second configuration, the sizes of portions of
the medical device 4000 are greater than the size of the opening.
For example, the size of the opening/incision in the skin can be
between 3 millimeters in length and 25 millimeters in length across
the opening. In some embodiments, the size of the medical device
4000 in the expanded second configuration is between 3 and 25
millimeters across the opening.
[0225] FIGS. 39-44 are posterior views of a spinal implant 4100
according to an embodiment of the invention inserted between
adjacent spinous processes S in a first lateral position (FIG. 41)
and a second lateral position (FIG. 43). The spinal implant 4100
includes an expandable member 4102, a sensor 4112 and a valve 4132.
The expandable member 4102 has an inner area (not shown), an outer
surface 4110, a support portion 4118, a proximal retention portion
4114 and a distal retention portion 4116. The expandable member
4102 is repeatably positionable in a first configuration (FIG. 40),
a second configuration (FIGS. 41, 43 and 44) and a third
configuration (FIG. 42). When in each configuration, the expandable
member 4102 has an associated volume, as will be discussed
below.
[0226] In use, the spinal implant 4100 is positioned in the
substantially contracted first configuration during insertion
and/or removal (see FIG. 40). As discussed above, the spinal
implant 4100 is inserted percutaneously between adjacent spinous
processes S. The distal retention portion 4116 of the expandable
member 4102 is inserted first and is moved past the spinous
processes S until the support portion 4118 is positioned between
the spinous processes S. When in the first configuration, the
support portion 4118 can be can be sized to account for ligaments
and tissue surrounding the spinous processes S. For purposes of
clarity, such surrounding ligaments and tissue are not
illustrated.
[0227] As illustrated in FIG. 41, once in position, the expandable
member 4102 is expanded into the second configuration by conveying
a fluid (not shown) from an area outside of the expandable member
4102 to the inner area of the expandable member 4102. The fluid is
conveyed by an expansion tool 4130, such as a catheter, that is
matingly coupled to the valve 4132. The valve 4132 can be any valve
suitable for sealably connecting the inner area of the expandable
member 4102 to an area outside of the expandable member 4102. For
example, in some embodiments, the valve 4132 can be, for example a
poppet valve, a pinch valve or a two-way check valve. In other
embodiments, the valve includes a coupling portion (not shown)
configured to allow the expansion tool 4130 to be repeatably
coupled to and removed from the valve 4132. For example, in some
embodiments, the valve 4132 can include a threaded portion
configured to matingly couple the expansion tool 4130 and the valve
4132.
[0228] The fluid is configured to retain fluidic properties while
resident in the inner area of the expandable member 4102. In this
manner, the spinal implant 4100 can be repeatably transitioned from
the expanded second configuration to the first configuration and/or
the third configuration by removing the fluid from the inner area
of the expandable member 4102. In some embodiments, the fluid can
be a biocompatible liquid having constant or nearly constant
properties. Such liquids can include, for example, saline solution.
In other embodiments, the fluid can be a biocompatible liquid
configured to have material properties that change over time while
still retaining fluidic properties sufficient to allow removal of
the fluid. For example, the viscosity of a fluid can be increased
by adding a curing agent or the like. In this manner, the fluid can
provide both the requisite structural support while retaining the
ability to be removed from the inner area of the expandable member
4102 via the valve 4132. In yet other embodiments, the fluid can be
a biocompatible gas.
[0229] The outer surface 4110 of the support portion 4118 can
distract the adjacent spinous processes S as the expandable member
4102 expands to the second configuration, as indicated by the
arrows shown in FIG. 41. In some embodiments, the support portion
4118 does not distract the adjacent spinous processes S. For
example, as discussed above, the adjacent spinous processes S can
be distracted by a trocar and/or any other device suitable for
distraction.
[0230] When in the second configuration, the outer surface 4110 of
the support portion 4118 is configured to engage the spinous
processes S for at least a portion of the range of motion of the
spinous processes S to prevent over-extension/compression of the
spinous processes S. In some embodiments, the engagement of the
spinous processes S by the outer surface 4110 of the support
portion 4118 is not continuous, but occurs upon spinal
extension.
[0231] When in the second configuration, the proximal retention
portion 4114 and the distal retention portion 4116 each have a size
S1 (shown in FIG. 45) that is greater than the vertical distance D1
(shown in FIG. 45) between the spinous processes. In this manner,
the proximal retention portion 4114 and the distal retention
portion 4116 are disposed adjacent the sides of spinous processes S
(i.e., either through direct contact or through surrounding
tissue), thereby limiting movement of the spinal implant 4100
laterally along a longitudinal axis of the support portion
4118.
[0232] The expandable member 4102 can be made from any number of
biocompatible materials, such as, for example, PET, Nylons,
cross-linked Polyethylene, Polyurethanes, and PVC. In some
embodiments, the chosen material can be substantially inelastic,
thereby forming a low-compliant expandable member 4102. In other
embodiments, the chosen material can have a higher elasticity,
thereby forming a high-compliant expandable member 4102. In yet
other embodiments, the expandable member 4102 can be made from a
combination of materials such that one portion of the expandable
member 4102, such as the support portion 4118, can be low-compliant
while other portions of the expandable member 4102, such as the
proximal retention portion 4114 and/or distal retention portion
4116 are more highly compliant. In yet other embodiments, a portion
of the expandable member 4102 can include a rigid, inflexible
material to provide structural stiffness. For example, the support
portion 4118 can be constructed of a composite material that
includes a rigid, inflexible material to facilitate distraction of
the adjacent spinous processes.
[0233] In some embodiments, the expandable member 4102 includes a
radiopaque material, such as bismuth, to facilitate tracking the
position of the spinal implant 4100 during insertion and/or
repositioning. In other embodiments, the fluid used to expand the
expandable member 4102 includes a radiopaque tracer to facilitate
tracking the position of the spinal implant 4100.
[0234] In the illustrated embodiment, the spinal implant 4100
includes a sensor 4112 coupled to the expandable member 4102. In
some embodiments, the sensor 4112 is a strain gauge sensor that
measures a force applied to the support portion 4118 of the
expandable member 4102. The sensor 4112 can include multiple strain
gauges to facilitate measuring multiple force quantities, such as a
compressive force and/or a tensile force. In other embodiments, the
sensor 4112 is a variable capacitance type pressure sensor
configured to measure a force and/or a pressure of the fluid
contained within the inner portion of the expandable member 4102.
In yet other embodiments, the sensor 4112 is a piezoelectric sensor
that measures a pressure of the fluid contained within the inner
portion of the expandable member 4102. In still other embodiments,
the spinal implant 4100 can include multiple sensors 4112 located
at various locations to provide a spatial profile of the force
and/or pressure applied to the expandable member 4102. In this
manner, a practitioner can detect changes in the patient's
condition, such those that may result in a loosening of the spinal
implant 4100.
[0235] In some embodiments, the sensor 4112 can be remotely
controlled by an external induction device. For example, an
external radio frequency (RF) transmitter (not shown) can be used
to supply power to and communicate with the sensor 4112. In other
embodiments, an external acoustic signal transmitter (not shown)
can be used to supply power to and communicate with the sensor
4112. In such an arrangement, for example, the sensor can include a
pressure sensor, of the types described above, for measuring a
pressure; an acoustic transducers, and an energy storage device.
The acoustic transducer converts energy between electrical energy
and acoustic energy. The energy storage device stores the
electrical energy converted by the acoustic transducer and supplies
the electrical energy to support the operation of the pressure
sensor. In this manner, acoustic energy from an external source can
be received and converted into electrical energy used to power the
pressure sensor. Similarly, an electrical signal output from the
pressure sensor can be converted into acoustic energy and
transmitted to an external source.
[0236] At times, the spinal implant 4100 may need to be
repositioned. Such repositioning can be required, for example, to
optimize the lateral position of the support portion 4118 during
the insertion process. In other instances, the spinal implant 4100
can require repositioning subsequent to the insertion process to
accommodate changes in the conditions of the patient. In yet other
instances, the spinal implant 4100 can be removed from the patient.
To allow for such repositioning and/or removal, the spinal implant
is repeatably positionable in the first configuration, the second
configuration and/or the third configuration. In FIG. 42, for
example, the expandable member 4102 is contracted to the third
configuration by removing all or a portion of the fluid contained
in the inner area, as described above. In this manner, the spinal
implant 4100 can be repositioned in a lateral direction, as
indicated by the arrow. Once in the desired position, the
expandable member is reexpanded to the second condition as
described above. Finally, as shown in FIG. 44, the expansion tool
4130 is removed from the valve 4132.
[0237] FIG. 45 is a lateral view of the spinal implant 4100
illustrated in FIGS. 39-44 inserted between adjacent spinous
processes S in a second configuration. Although FIG. 45 only shows
the proximal retention portion 4114 of the expandable member 4102,
it should be understood that the distal retention portion 4116 has
characteristics and functionality similar to those described below
for proximal retention portion 4114. As illustrated, the proximal
retention portion 4114 has a size S1 that is greater than the
vertical distance D1 between the spinous processes S. In this
manner, the proximal retention portion 4114 and the distal
retention portion 4116 limit the lateral movement of the spinal
implant 4100 when in the second configuration, as discussed
above.
[0238] FIG. 46 is a lateral view of a spinal implant 4200 according
to an embodiment of the invention inserted between adjacent spinous
processes and in a second configuration. Similar to the spinal
implant 4100 discussed above, the spinal implant 4200 includes an
expandable member 4202 and a valve 4232. The expandable member 4202
has a support portion (not shown), a proximal retention portion
4214 and a distal retention portion (not shown). The expandable
member 4202 is repeatably positionable in a first configuration, a
second configuration and/or a third configuration. When in each
configuration, the expandable member 4202 has an associated volume,
as discussed above.
[0239] In the illustrated embodiment, the proximal retention
portion 4214 of the expandable member 4202 has a first radial
extension 4236, a second radial extension 4238 and a third radial
extension 4240. As illustrated, the distance S1 between the ends of
the radial extensions is greater than the vertical distance D1
between the spinous processes S. In this manner, the proximal
retention portion 4214 and the distal retention portion limit the
lateral movement of the spinal implant 4200 when in the second
configuration. In some embodiments, the proximal retention portion
and the distal retention portion can assume a variety of different
shapes.
[0240] FIGS. 47 and 48 are front views of a spinal implant 4300
according to an embodiment of the invention in a first
configuration and a second configuration, respectively. The spinal
implant 4300 includes a proximal expandable member 4304, a distal
expandable member 4306, a support member 4308, a sensor 4312 and a
valve 4332. The support member 4308 has an inner area (not shown)
and an outer surface 4310. The outer surface 4310 is configured to
contact the spinous processes (not shown). In some embodiments, the
support member 4308 distracts the adjacent spinous processes. In
other embodiments, the support member 4308 does not distract the
adjacent spinous processes. In yet other embodiments, the
engagement of the spinous processes by the support member 4308 is
not continuous, but occurs upon spinal extension.
[0241] The support member 4308 has a proximal portion 4324, to
which the proximal expandable member 4304 is coupled, and a distal
portion 4326, to which the distal expandable member 4306 is
coupled. The proximal expandable member 4304 and the distal
expandable member 4306 are each repeatably positionable in a first
configuration (FIG. 47) and a second configuration (FIG. 48). As
described above, the first configuration represents a substantially
contracted condition in which the proximal expandable member 4304
and the distal expandable member 4306 each have a minimal volume.
When the spinal implant 4300 is in the first configuration, it can
be inserted, repositioned and/or removed. In the illustrated
embodiment, the proximal expandable member 4304 and the distal
expandable member 4306 are each contained within the inner area of
the support member 4308 when the spinal implant 4300 is in the
first configuration. In some embodiments, the proximal expandable
member 4304 and the distal expandable member 4306 are not contained
within the support member 4308.
[0242] Conversely, the second configuration represents an expanded
condition in which the proximal expandable member 4304 and the
distal expandable member 4306 each have a large volume. When the
spinal implant 4300 is in the second configuration, the proximal
expandable member 4304 and the distal expandable member 4306 each
have a size that is greater than the vertical distance between the
spinous processes, as described above. In this manner, the proximal
expandable member 4304 and the distal expandable member 4306 engage
the spinous processes, thereby limiting the lateral movement of the
spinal implant 4300.
[0243] The proximal expandable member 4304 and the distal
expandable member 4306 are expanded into the second configuration
by conveying a fluid (not shown) from an area outside of each
expandable member 4304, 4306 to an inner area defined by each
expandable member 4304, 4306. The fluid is conveyed through a valve
4332, as described above. In the illustrated embodiment, the inner
area of the proximal expandable member 4304, the inner area of the
distal expandable member 4306 and the inner area of the support
member 4308 are in fluid communication with each other to form a
single inner area. As such, the fluid can be conveyed to both the
inner area of the proximal expandable member 4304 and the inner
area of the distal expandable member 4306 by a single valve 4332.
In some embodiments, the inner areas of the proximal expandable
member 4304 and the distal expandable member 4306 are not in fluid
communication. In such an arrangement, each expandable member can
be independently transformed between configurations.
[0244] The support member 4308 can be made from any number of
biocompatible materials, such as, for example, stainless steel,
plastic, polyetheretherketone (PEEK), carbon fiber, ultra-high
molecular weight (UHMW) polyethylene, and the like. The material of
the support member 4308 can have a tensile strength similar to or
higher than that of bone. In some embodiments, the support member
4308 is substantially rigid. In other embodiments, the support
member 4308 or portions thereof is elastically deformable, thereby
allowing it to conform to the shape of the spinous processes. In
yet other embodiments, the support member 4308 includes a
radiopaque material, such as bismuth, to facilitate tracking the
position of the spinal implant 4300 during insertion and/or
repositioning.
[0245] The proximal expandable member 4304 and the distal
expandable member 4306 can be made from any number of biocompatible
materials, as discussed above. The proximal expandable member 4304
and the distal expandable member 4306 can be coupled to the support
member by an suitable means, such as a biocompatible adhesive.
[0246] In the illustrated embodiment, the spinal implant 4300
includes a sensor 4312 coupled to the support member 4308. As
described above, the sensor 4312 can be configured to measure
multiple force quantities and/or a pressure of the fluid contained
within the proximal expandable member 4304 and the distal
expandable member 4306.
[0247] Although the spinal implants 4100, 4200 and 4300 are shown
and described above as be movable from a retracted configuration to
an expanded configuration by conveying a fluid to an inner area of
an expandable member, in some embodiments, an implant can be
configured to receive any suitable substance to move from a
retracted configuration to an expanded configuration. For example,
in some embodiments, an implant can include an expandable portion
configured to receive a mixture of solid particles contained within
a carrier fluid (e.g., a slurry). In other embodiments, an implant
can include an expandable portion configured to be filled solely
with solid particles to move from a retracted configuration to an
expanded configuration. In this manner, the solid particles can
form a substrate within the expandable portion that is
incompressible and/or more rigid than a liquid or gas.
[0248] The solid particles can be of any suitable size and/or
shape. In some embodiments, for example, the solid particles can be
approximately spherical particles having a diameter of between
0.010 mm and 0.100 mm. In other embodiments, the solid particles
can include one or more flat surfaces. In yet other embodiments,
the solid particles can be irregularly shaped.
[0249] The solid particles can be constructed from any suitable
biocompatible material, such as, for example, PET, Nylons,
cross-linked Polyethylene, Polyurethanes, and PVC. In some
embodiments, the solid particles can be substantially inelastic,
thereby forming a low-compliant substrate within the expandable
portion of the implant. In other embodiments, the solid particles
can have a higher elasticity, thereby forming a high-compliant
filler within the expandable portion of the implant. In yet other
embodiments, the solid particles can be constructed from a
combination of materials such that the characteristics of the
filler within the expandable portion of the implant can vary
spatially.
[0250] Similarly, in some embodiments, the solid particles can be
constructed from a material having a high rigidity (i.e., a high
shear modulus). In this manner, the solid particles can form a
substrate within the expandable portion that has a high resistance
to deformation when exposed to a shear stress. In other
embodiments, the solid particles can be constructed from a material
having a low rigidity. In such embodiments, for example, the solid
particles can form a substrate with the expandable portion that can
deform when compressed during extension of the spinal column.
[0251] In some embodiments, the materials from which the solid
particles and the expandable portion are constructed can be
selected cooperatively such that the implant, when filled, has
suitable strength, rigidity, elasticity and the like. For example,
in some embodiments, an implant includes an expandable portion
constructed from a low-compliant material that is configured to be
expanded by flexible solid particles. In other embodiments, an
implant includes an expandable portion constructed from a
low-compliant material that is configured to be expanded by rigid
solid particles. In yet other embodiments, an implant includes an
expandable portion constructed from a high-compliant material that
is configured to be expanded by flexible solid particles. In yet
other embodiments, an implant includes an expandable portion
constructed from a high-compliant material that is configured to be
expanded by rigid solid particles.
[0252] In some embodiments, the solid particles and/or mixture of
solid particles and carrier fluid can be conveyed into and/or
removed from the expandable portion of the implant by an expansion
tool and via a valve, as described above. In other embodiments, the
solid particles and/or mixture of solid particles and carrier fluid
can be removed from the expandable portion of the implant by
puncturing the expandable portion and applying a vacuum to withdraw
the solid particles and/or mixture of solid particles and carrier
fluid. In yet other embodiments, the solid particles and/or mixture
of solid particles and carrier fluid can be removed from the
expandable portion of the implant by puncturing the expandable
portion and applying a pressure against an outer portion of the
expandable portion to cause the solid particles and/or mixture of
solid particles and carrier fluid to be expelled within the
body.
[0253] In some embodiments, the solid particles can be configured
to absorb liquid to expand the expandable portion of an implant.
For example, in some embodiments, an expandable portion of an
implant can include solid particles constructed from a hydrogel.
When the implant is disposed between adjacent spinous processes, a
liquid can be conveyed to the expandable portion of the implant,
which is then absorbed by the hydrogel particles. Accordingly, the
size of the hydrogel particles will increase, thereby expanding the
expandable portion of the implant.
[0254] Similarly, in some embodiments, a kit can include an implant
having an expandable portion, multiple sets of solid particles, and
multiple different liquids. The different sets of solid particles
can have different characteristics, such as, for example, a size, a
shape, and/or an absorption coefficient. Similarly, the different
liquids can have different characteristics, such as, for example,
viscosity, density and/or an absorption coefficient. In this
manner, a user can select a particular set of particles for
inclusion in the expandable portion of the implant and a particular
liquid for use in expanding the solid particles.
[0255] FIGS. 49 and 50 are schematic illustrations of a posterior
view of a medical device 3000 according to an embodiment of the
invention disposed between two adjacent spinous processes S in a
first configuration and a second configuration, respectively. The
medical device 3000 includes a support member 3002, a proximal
retention member 3010 and a distal retention member 3012. The
support member 3002 has a proximal portion 3004 and a distal
portion 3006, and is configured to be disposed between the spinous
processes S to prevent over-extension/compression of the spinous
processes S. In some embodiments, the support member 3002 distracts
the adjacent spinous processes S. In other embodiments, the support
member 3002 does not distract the adjacent spinous processes S.
[0256] The proximal retention member 3010 has a first configuration
in which it is substantially disposed within the proximal portion
3004 of the support member 3002, as illustrated in FIG. 49.
Similarly, the distal retention member 3012 has a first
configuration in which it is substantially disposed within the
distal portion 3006 of the support member 3002. When the proximal
retention member 3010 and the distal retention member 3012 are each
in their respective first configuration, the medical device 3000
can be inserted between the adjacent spinous processes S.
[0257] The proximal retention member 3010 can be moved from the
first configuration to a second configuration in which a portion of
it is disposed outside of the support member 3002, as illustrated
in FIG. 50. Similarly, the distal retention member 3012 can be
moved from the first configuration to a second configuration. When
each is in their respective second configuration, the proximal
retention member 3010 and the distal retention member 3012 limit
lateral movement of the support member 3002 with respect to the
spinous processes S by contacting the spinous processes S (i.e.,
either directly or through surrounding tissue). For purposes of
clarity, the tissue surrounding the spinous processes S is not
illustrated.
[0258] In use, the adjacent spinous processes S can be distracted
prior to inserting the medical device 3000 into the patient. When
the spinous processes S are distracted, a trocar (not shown in FIG.
49 or 50) can be used to define an access passageway (not shown in
FIGS. 49 and 50) for the medical device 3000. In some embodiments,
the trocar can be used to define the passage as well as to distract
the spinous processes S.
[0259] Once an access passageway is defined, the medical device
3000 is inserted percutaneously and advanced, distal portion 3006
first, between the spinous processes S. The medical device 3000 can
be inserted from the side of the spinous processes S (i.e., a
posterior-lateral approach). The use of a curved shaft assists in
the use of a lateral approach to the spinous processes S. Once the
medical device 3000 is in place between the spinous processes S,
the proximal retention member 3010 and the distal retention member
3012 are moved to their second configurations, either serially or
simultaneously. In this manner, lateral movement of the support
member 3002 with respect to the spinous processes S is limited.
[0260] When it is desirable to change the position of the medical
device 3000, the proximal retention member 3010 and the distal
retention member 3012 are moved back to their first configurations,
thereby allowing the support member 3002 to be moved laterally.
Once the support member 3002 is repositioned, the medical device
3000 can be returned to the second configuration. Similarly, when
it is desirable to remove the medical device 3000, proximal
retention member 3010 and the distal retention member 3012 are
moved to their first configurations, thereby allowing the support
member 3002 to be removed.
[0261] In some embodiments, the medical device 3000 is inserted
percutaneously (i.e., through an opening in the skin) and in a
minimally-invasive manner. For example, as discussed in detail
herein, the overall sizes of portions of the medical device 3000
can be increased by moving the proximal retention member 3010 and
the distal retention member 3012 to their respective second
configurations after the medical device 3000 is inserted between
the adjacent spinous processes S. When in the expanded second
configuration, the sizes of portions of the medical device 3000 can
be greater than the size of the opening. For example, the size of
the opening/incision in the skin can be between 3 millimeters in
length and 25 millimeters in length across the opening. In some
embodiments, the size of the medical device 3000 in the expanded
second configuration is between 3 and 25 millimeters across the
opening.
[0262] FIGS. 51-56 illustrate a spinal implant 3100 according to an
embodiment of the invention. FIGS. 51 and 52 are perspective views
of the spinal implant 3100 in a first configuration and a second
configuration, respectively. The spinal implant 3100 includes a
support member 3102, a proximal retention member 3110 and a distal
retention member 3112. The support member 3102 is positioned
between adjacent spinous processes S, as illustrated in FIGS. 53
and 54. As shown in FIGS. 51 and 52, the proximal retention member
3110 and the distal retention member 3112 are each repeatably
positionable in a first configuration in which they are
substantially disposed within the support member 3102 (FIG. 51),
and a second configuration in which a portion of each retention
member 3110, 3112 is disposed outside of the support member 3102
(FIG. 52). When the spinal implant 3100 is in the first
configuration, it can be inserted between the adjacent spinous
processes S, repositioned between the adjacent spinous processes
and/or removed from the patient. When the spinal implant 3100 is in
the second configuration, its lateral movement is limited, thereby
allowing the desired position of the support member 3102 to be
maintained.
[0263] In some embodiments, the support member 3102 distracts the
adjacent spinous processes S. In other embodiments, the support
member 3102 does not distract the adjacent spinous processes S. In
yet other embodiments, the engagement of the spinous processes S by
the support member 3102 is not continuous, but occurs upon spinal
extension.
[0264] The support member 3102 can be made from any number of
biocompatible materials, such as, for example, stainless steel,
plastic, polyetheretherketone (PEEK), carbon fiber, ultra-high
molecular weight (UHMW) polyethylene, and the like. The material of
the support member 3102 can have a tensile strength similar to or
higher than that of bone. In some embodiments, the support member
3102 is substantially rigid. In other embodiments, the support
member 3102 or portions thereof is elastically deformable, thereby
allowing it to conform to the shape of the spinous processes. In
yet other embodiments, the support member 3102 includes a
radiopaque material, such as bismuth, to facilitate tracking the
position of the spinal implant 3100 during insertion and/or
repositioning.
[0265] In the illustrated embodiment, the spinal implant 3100
includes a sensor 3124 coupled to the support member 3102. In some
embodiments, the sensor 3124 is a strain gauge sensor that measures
a force applied to the support member 3102. In some embodiments,
the sensor 3124 can include multiple strain gauges to facilitate
measuring multiple force quantities, such as a compressive force
and/or a bending moment. In other embodiments, the sensor 3124 is a
variable capacitance type pressure sensor configured to measure a
force and/or a pressure applied to the support member 3102. In yet
other embodiments, the sensor 3124 is a piezoelectric sensor that
measures a force and/or a pressure applied to the support member
3102. In still other embodiments, the spinal implant 3100 can
include multiple sensors located at various locations to provide a
spatial profile of the force and/or pressure applied to the support
member 3102. In this manner, a practitioner can detect changes in
the patient's condition, such those that may result in a loosening
of the spinal implant.
[0266] In some embodiments, the sensor 3124 can be remotely
controlled by an external induction device. For example, an
external radio frequency (RF) transmitter (not shown) can be used
to supply power to and communicate with the sensor 3124. In other
embodiments, an external acoustic signal transmitter (not shown)
can be used to supply power to and communicate with the sensor
3124. In such an arrangement, for example, the sensor can include a
pressure sensor, of the types described above, for measuring a
pressure; an acoustic transducers, and an energy storage device.
The acoustic transducer converts energy between electrical energy
and acoustic energy. The energy storage device stores the
electrical energy converted by the acoustic transducer and supplies
the electrical energy to support the operation of the pressure
sensor. In this manner, acoustic energy from an external source can
be received and converted into electrical energy used to power the
pressure sensor. Similarly, an electrical signal output from the
pressure sensor can be converted into acoustic energy and
transmitted to an external source.
[0267] The support member 3102 includes a sidewall 3108 that
defines an inner area 3120 and multiple openings 3114 that connect
the inner area 3120 to an area outside of the support member 3102.
When the spinal implant 3100 is in the first configuration, the
proximal retention member 3110 and the distal retention member 3112
are substantially disposed within the inner area 3120 of the
support member 3102, as shown in FIG. 51. When the spinal implant
3100 is in the second configuration, a portion of each of the
proximal retention member 3110 and the distal retention member 3112
extends through the openings 3114 to an area outside of the support
member 3102. In the second configuration, the proximal retention
member 3110 and the distal retention member 3112 engage the
adjacent spinous processes, thereby limiting lateral movement of
the spinal implant 3100.
[0268] The proximal retention member 3110 includes a first elongate
member 3130 and a second elongate member 3132. Similarly, the
distal retention member 3112 includes a first elongate member 3131
and a second elongate member 3133. As illustrated in FIG. 56, which
shows is a cross-sectional plan view of the proximal portion 3104
of the support member 3102, the first elongate member 3130 is
slidably disposed within a pocket 3134 defined by the second
elongate member 3132. A biasing member 3136, such as a spring or an
elastic member, is disposed within the pocket 3134 and is coupled
to the first elongate member 3130 and the second elongate member
3132. In this manner, the retention members can be biased in the
second configuration. In other embodiments, the biasing member 3136
can be configured to bias the retention members in the first
configuration. In yet other embodiments, the retention members do
not include a biasing member, but instead use other mechanisms to
retain a desired configuration. Such mechanisms can include, for
example, mating tabs and slots configured to lockably engage when
the retention members are in a desired configuration.
[0269] In use, the spinal implant 3100 is positioned in the first
configuration during insertion, removal or repositioning. As
discussed above, the spinal implant 3100 is inserted percutaneously
between adjacent spinous processes. The distal portion 3106 of the
support member 3102 is inserted first and is moved past the spinous
processes until the support member 3102 is positioned between the
spinous processes. The support member 3102 can be sized to account
for ligaments and tissue surrounding the spinous processes S. In
some embodiments, the support member 3102 contacts the spinous
processes between which it is positioned during a portion of the
range of motion of the spinous processes S. In some embodiments,
the support member 3102 of spinal implant 3100 is a fixed size and
is not compressible or expandable. In yet other embodiments, the
support member 3102 can compress to conform to the shape of the
spinous processes S. Similarly, in some embodiments, the proximal
retention member 3110 and the distal retention member 3112 are
substantially rigid. In other embodiments, the retention members or
portions thereof are elastically deformable, thereby allowing them
to conform to the shape of the spinous processes.
[0270] In the illustrated embodiment, the spinal implant 3100 is
held in the first configuration by an insertion tool (not shown)
that overcomes the force exerted by the biasing member 3136,
thereby disposing a portion of the first elongate member 3130
within the pocket 3134 of the second elongate member 3132. In this
manner, the spinal implant 3100 can be repeatedly moved from the
first configuration to the second configuration, thereby allowing
it to be repositioned and/or removed percutaneously. As illustrated
in FIG. 55, the first elongate member 3130 and the second elongate
member 3132 each include notches 3138 configured to receive a
portion of the insertion tool. When the insertion tool is released,
the biasing member 3136 is free to extend, thereby displacing a
portion of the first elongate member 3130 out of the pocket 3134 of
the second elongate member 3132. In this manner, portions of both
the first elongate member 3130 and the second elongate member 3132
are extended through the adjacent openings 3114 and to an area
outside of the support member 3102. In some embodiments, the
proximal retention member 3110 and the distal retention member 3112
are transitioned between their respective first and second
configurations simultaneously. In other embodiments, the proximal
retention member 3110 and the distal retention member 3112 are
transitioned between their first and second configurations
serially.
[0271] As illustrated, the first elongate member 3130 and the
second elongate member 3132 each include one or more tabs 3140 that
engage the side wall 3108 of the support member 3102 when in the
second configuration, thereby ensuring that the first and second
elongate members remain coupled to each other and that portions of
the first and second elongate members remain suitably disposed
within the support member 3102. In other embodiments, the first
elongate member 3130 and the second elongate member 3132 are
coupled to each other by other suitable mechanisms, such as mating
tabs and slots configured to engage when the retention member
reaches a predetermined limit of extension.
[0272] FIGS. 57-59 are cross-sectional views of a spinal implant
3200 according to an embodiment of the invention. FIG. 57
illustrates a cross-sectional front view of the spinal implant 3200
in a second configuration, while FIGS. 58 and 59 illustrate a
cross-sectional plan view of the spinal implant 3200 in the second
configuration and a first configuration, respectively. The
illustrated spinal implant 3200 includes a support member 3202, a
retention member 3210 and a rotating member 3250. Although shown
and described as including only a single retention member 3210,
some embodiments can include one or more additional retention
members having characteristics and functionality similar to those
described for the retention member 3210.
[0273] As shown in FIGS. 58 and 59, the retention member 3210 is
repeatably positionable in a first configuration in which it is
substantially disposed within the support member 3202, and a second
configuration in which a portion the retention member 3210 is
disposed outside of the support member 3102. When the spinal
implant 3200 is in the first configuration, it can be inserted
between adjacent spinous processes, repositioned between adjacent
spinous processes and/or removed from the patient. When the spinal
implant 3200 is in the second configuration, its lateral movement
is limited, thereby allowing the desired position of the support
member 3202 to be maintained.
[0274] The support member 3202 includes a sidewall 3208 that
defines an inner area 3220 and multiple openings 3214 that connect
the inner area 3220 to an area outside of the support member 3202.
When the spinal implant 3200 is in the first configuration, the
retention member 3210 is substantially disposed within the inner
area 3220 of the support member 3202, as shown in FIG. 59. When the
spinal implant 3200 is in the second configuration, a portion of
the proximal retention member 3210 extends through the openings
3214 to an area outside of the support member 3202. In the second
configuration, the retention member 3210 is disposed adjacent the
spinous processes, thereby limiting lateral movement of the spinal
implant 3200.
[0275] The retention member 3210 includes an elongate member 3228
having two end portions 3244, a central portion 3242, and a
longitudinal axis L1 (shown in FIG. 57). A portion of the elongate
member 3228 is flexible such that it can be wound along the
rotating member 3250, as described below. In some embodiments, the
elongate member 3228 is monolithically formed such that it is
flexible enough to be wound along the rotating member 3250 yet
rigid enough to limit lateral movement of the support member 3202
when positioned in the second configuration. In other embodiments,
the elongate member 3228 includes separate components that are
coupled together to form the elongate member 3228. For example, the
central portion 3242 of the elongate member 3228 can be a distinct
component having a greater amount of flexibility, while the end
portions 3244 can be distinct components having a greater amount of
rigidity.
[0276] In the illustrated embodiment, elongate member 3228 has one
or more tabs 3240 that engage the side wall 3208 of the support
member 3202 when in the second configuration, thereby ensuring that
the elongate member 3228 does not freely extend entirely outside of
the support member 3202. In other embodiments, a portion of the
elongate member 3228 is retained within the support member 3202 by
other suitable mechanisms. For example, the width of the central
portion 3242 of the elongate member 3228 can be greater than the
width of the openings 3214, thereby ensuring that a portion of the
elongate member 3228 will remain within the support member
3202.
[0277] The rotating member 3250 defines an outer surface 3252 and a
slot 3254 through which the elongate member 3228 is disposed. The
rotating member 3250 has a longitudinal axis L2 (shown in FIG. 57)
about which it rotates. As illustrated in FIG. 59, as the rotating
member 3250 rotates, the elongate member 3228 is wound along the
outer surface 3252 of the rotating member 3250. This causes the
elongate member 3228 to move along its longitudinal axis L1,
thereby causing the end portions 3244 of the elongate member 3228
to be retracted inwardly through the openings 3214. In this manner,
the retention member 3210 can be repeatedly transitioned between
the first configuration and the second configuration.
[0278] In some embodiments, the rotating member 3250 is rotated
using an insertion tool (not shown) that includes a ratchet
mechanism. The insertion tool can rotate the rotating member 3250
in a number of different ways, such as, for example, manually,
pneumatically or electronically.
[0279] FIGS. 60-63 are cross-sectional views of a spinal implant
3300 according to an embodiment of the invention. FIG. 60
illustrates a cross-sectional front view of the spinal implant 3300
in a second configuration, while FIGS. 61-63 illustrate a
cross-sectional plan view of the spinal implant 3300 in the second
configuration, a first configuration, and a third configuration,
respectively. The illustrated spinal implant 3300 includes a
support member 3302 and a retention member 3310. Although shown and
described as including only a single retention member 3310, some
embodiments can include one or more additional retention members
having characteristics and functionality similar to those described
for the retention member 3310.
[0280] As shown in FIGS. 61-63, the retention member 3310 is
repeatably positionable in a first configuration, a second
configuration and a third configuration. A portion the retention
member 3310 is disposed outside of the support member 3302 when
positioned in the second configuration. The retention member 3310
is substantially disposed within the support member 3202 when
positioned in each of the first and third configurations. As
illustrated in FIGS. 62 and 63, the orientation of the retention
member 3310 differs between the first and third configurations. In
this manner, the position of the spinal implant 3300 can be
positioned appropriately depending on the direction in which it is
being moved. For example, the spinal implant 3300 may be positioned
in the first configuration to facilitate lateral movement of the
support member 3302 in a distal direction, such as during
insertion. Conversely, the spinal implant 3300 may be positioned in
the third configuration to facilitate lateral movement of the
support member 3302 in a proximal direction, such as during
removal.
[0281] The support member 3302 includes a sidewall 3308 that
defines an inner area 3320 and multiple openings 3314 that connect
the inner area 3320 to an area outside of the support member 3302.
When the spinal implant 3300 is in the second configuration, a
portion of the proximal retention member 3310 extends through the
openings 3314 to an area outside of the support member 3302.
[0282] The retention member 3310 includes a first elongate member
3330, a second elongate member 3332, and a hinge 3360 having a
longitudinal axis L2 (shown in FIG. 60). Each of the first elongate
member 3330 and the second elongate member 3332 has a distal end
portion 3344 that extends through the openings 3314 when the spinal
implant 3300 is in the second configuration and a proximal end
portion 3346 that is pivotally coupled to the hinge 3360. In use,
the hinge 3360 moves in a direction normal to its longitudinal axis
L2, as indicated by the arrows in FIGS. 62 and 63. The motion of
the hinge is guided by a slot 3362 defined by the side wall 3308 of
the support member 3302. The movement of the hinge 3360 allows the
each of the first elongate member 3330 and the second elongate
member 3332 to rotate about the longitudinal axis L2 of the hinge
3360, thereby positioning the distal end portion 3344 of each
elongate member substantially within the inner area 3320 of the
support member 3302.
[0283] In some embodiments, the slot 3362 includes detents or any
other suitable mechanism (not shown) to maintain the hinge 3360 in
the desired position. In other embodiments the hinge 3360 includes
a biasing member (not shown) configured to bias the hinge 3360 in
one of the first, second, or third configurations. In yet other
embodiments, the elongate members include other suitable mechanisms
to retain the retention member in a desired configuration. Such
mechanisms can include, for example, mating tabs and slots
configured to lockably engage when the elongate members are in a
desired configuration.
[0284] In some embodiments, the first elongate member 3330 and the
second elongate member 3332 are monolithically formed of a
substantially rigid material. In other embodiments, the first
elongate member 3330 and the second elongate member 3332 include
separate components having different material properties. For
example, the distal end portion 3344 can be formed from a material
having a greater amount of flexibility, while the proximal end
portion 3346 can be formed from a substantially rigid material. In
this manner, movement of the spinal implant 3300 is not restricted
when a portion of the distal end portion 3344 protrudes from the
openings 3314 in either the first configuration or the third
configuration.
[0285] FIGS. 64 and 65 are cross-sectional front views of a spinal
implant 3400 according to an embodiment of the invention. The
illustrated spinal implant 3400 includes a support member 3402, a
retention member 3410 and a rotating member 3450. As shown in FIGS.
64 and 65, the retention member 3410 is repeatably positionable in
a first configuration in which it is substantially disposed within
the support member 3402, and a second configuration in which a
portion the retention member 3410 is disposed outside of the
support member 3402. Although shown and described as including only
a single retention member 3410, some embodiments include one or
more additional retention members having characteristics and
functionality similar to those described for the retention member
3410.
[0286] The support member 3402 includes a sidewall 3408 that
defines an inner area 3420 and multiple openings 3414 that connect
the inner area 3420 to an area outside of the support member 3402.
When the spinal implant 3400 is in the second configuration, a
portion of the proximal retention member 3410 extends through the
openings 3414 to an area outside of the support member 3402.
[0287] The retention member 3410 includes a first elongate member
3430 and a second elongate member 3432, each having a distal end
portion 3444 that extends through the openings 3414 when the spinal
implant 3400 is in the second configuration, a proximal end portion
3446, and a longitudinal axis L1. As illustrated, the proximal end
portions 3346 are coupled by two elastic members 3468, such as a
spring or an elastic band. In some embodiments, the proximal end
portions 3346 are coupled by a single elastic member. In other
embodiments, the proximal end portions 3346 are indirectly coupled
via the rotating member 3450. In such an arrangement, for example,
a biasing member can be placed between the sidewall of the support
member and each elongate member, thereby biasing each elongate
member against the rotating member.
[0288] In the illustrated embodiment, the elongate members each
include one or more tabs 3440 that engage the side wall 3408 of the
support member 3402 when in the second configuration, thereby
ensuring that the elongate members 3430, 3432 does not freely
extend entirely outside of the support member 3402. In other
embodiments, the elongate members do not include tabs, but are
retained within the support member 3402 solely by the elastic
members 3468. In yet other embodiments, the width of a portion of
the elongate members can be greater than the width of the openings
3414, thereby ensuring that the elongate members will remain within
the support member 3402.
[0289] The rotating member 3450 defines an outer surface 3452
having an eccentric shape and includes a longitudinal axis (not
shown) about which it rotates. As illustrated in FIGS. 64 and 65,
as the rotating member 3450 rotates about its longitudinal axis, a
portion of the proximal end portion 3346 of the first elongate
member 3430 and the second elongate member 3432 engage the outer
surface 3452 of the rotating member 3250. This causes the first
elongate member 3430 and the second elongate member 3432 to move
along their respective longitudinal axes L1, thereby causing the
end portions 3444 of each elongate member to be extended outwardly
through the openings 3414, as indicated by the arrows in FIG. 64.
In this manner, the retention member 3410 can be repeatedly
transitioned between the first configuration and the second
configuration.
[0290] In some embodiments, the rotating member 3450 is rotated
using an insertion tool (not shown) that includes a ratchet
mechanism. The insertion tool can rotate the rotating member 3450
in a number of different ways, such as, for example, manually,
pneumatically or electronically.
[0291] FIGS. 66 and 67 illustrate a spinal implant 3500 according
to an embodiment of the invention. FIG. 66 is a cross-sectional
front view of the spinal implant 3500 in a second configuration.
FIG. 67 is a cross-sectional plan view of the spinal implant 3500
taken along section A-A. The spinal implant 3500 includes a support
member 3502 and a retention member 3510. Although only shown as
being in a second or expanded configuration, it is understood from
the previous descriptions that the retention member 3510 is
repeatably positionable in a first configuration in which it is
substantially disposed within the support member 3502, and the
second configuration in which a portion the retention member 3510
is disposed outside of the support member 3502.
[0292] As illustrated, the retention member 3510 includes a first
elongate member 3530 and a second elongate member 3532. The first
elongate member 3530 is slidably disposed within a pocket 3534
defined by the second elongate member 3532. The first elongate
member 3530 and the second elongate member 3532 each include one or
more tabs 3540 that are coupled to the side wall 3508 of the
support member 3502 by one or more biasing members 3536. In this
manner, the retention member 3510 is biased in the first or
retracted configuration. In other embodiments, the biasing members
3536 can be configured to bias the retention member 3510 in the
second configuration. In yet other embodiments, the retention
member 3510 is not retained by a biasing member 3536, but rather
uses other suitable mechanisms to retain the desired
configuration.
[0293] In use, the retention member 3510 is transitioned from the
first configuration to the second configuration by supplying a
pressurized fluid (not shown) to the pocket 3534 via valve 3570.
The pressure exerted by the fluid on each of the first elongate
member 3530 and the second elongate member 3532 overcomes the force
exerted by the biasing members 3536, thereby causing a portion the
first elongate member 3530 to extend outwardly from the pocket 3534
of the second elongate member 3132, thereby allowing a portion of
each elongate member to extend through the adjacent openings 3514
and to an area outside of the support member 3502. Similarly, the
retention member 3510 is transitioned from the second configuration
to the first configuration by opening the valve 3570 and relieving
the pressure within the pocket 3534. In this manner, the spinal
implant 3500 can be repeatedly moved from the first configuration
to the second configuration, thereby allowing it to be repositioned
and/or removed percutaneously.
[0294] FIGS. 68 and 69 illustrate perspective views of a spinal
implant 3600 according to an embodiment of the invention. The
spinal implant 3600 includes a support member 3602, a proximal
retention member 3610, a distal retention member 3612, and an
elastic member 3668. The support member 3602 defines a longitudinal
axis L1 and has a sidewall 3608 that defines an inner area 3620 and
has an outer surface 3616. As illustrated in FIG. 69, the outer
surface 3616 defines an area A normal to the longitudinal axis L1.
As shown, the proximal retention member 3610 and the distal
retention member 3612 are each repeatably positionable in a first
configuration in which they are substantially disposed within the
area A (FIG. 69), and a second configuration in which a portion of
each retention member 3610, 3612 is disposed outside of the area A
(FIG. 68).
[0295] As illustrated, the proximal retention member 3610 and the
distal retention member 3612 are coupled by the elastic member
3668, a portion of which is disposed within the inner area 3620 of
the support member 3602. In the illustrated embodiment, the elastic
member 3668 has a sidewall 3674 that defines a lumen 3676. In other
embodiments, the elastic member can be, for example, a spring, an
elastic band, or any other suitable device for elastically coupling
the proximal retention member 3610 and the distal retention member
3612.
[0296] The proximal retention member 3610 includes a first elongate
member 3630 and a second elongate member 3632, each of which are
pivotally coupled to a connection member 3678 by a hinge 3660.
Similarly, the distal retention member 3612 includes a first
elongate member 3631 and a second elongate member 3633 each of
which are pivotally coupled to a connection member 3678 by a hinge
3660.
[0297] As illustrated in FIG. 68, when the spinal implant 3600 is
in the second configuration, the elastic member 3668 exerts a
biasing force on each connection member 3678, thereby causing the
connection members 3678 to remain adjacent to the support member
3602. In this configuration, the first elongate member 3630 and the
second elongate member 3632 are fully extended. The spinal implant
3600 is transitioned from the second configuration to the first
configuration by stretching the elastic member 3668, which allows
the connection members 3678 to be disposed apart from the support
member 3602, thereby allowing the elongate members to move within
the area A, as illustrated in FIG. 69. The support member 3602
includes slots 3672 in which the end portion of each elongate
member can be disposed to maintain the spinal implant 3600 in the
first configuration.
[0298] The elastic member 3668 can be stretched by an insertion
tool (not shown), a portion of which can be configured to be
disposed within the lumen 3676 of the elastic member 3668. For
example, a first portion of an insertion tool can engage the
connection member 3678 of the proximal retention member 3610 while
a second portion of the insertion tool can engage the connection
member 3678 of the distal retention member 3612. The tool can then
be configured to exert an outward force on each of the connection
members 3678, thereby stretching the elastic member 3668 and
allowing the spinal implant to transition from the second
configuration to the first configuration.
[0299] While the spinal implants are shown and described above as
having one or more retention members that extend substantially
symmetrically from a support member when in a second configuration,
in some embodiments, a spinal implant includes a retention member
that extends asymmetrically from a support member when in a second
configuration. For example, FIGS. 70-74 illustrate a spinal implant
3700 according to an embodiment of the invention that includes a
proximal retention member 3710 and a distal retention member 3712
that extend asymmetrically from a support member 3702. As shown in
FIGS. 70-74, the proximal retention member 3710 and the distal
retention member 3712 are each repeatably positionable in a first
configuration in which they are substantially disposed within the
support member 3702, and a second configuration in which a portion
each is disposed outside of the support member 3702.
[0300] The support member 3702 includes a sidewall 3708 that
defines an inner area 3720 and two openings 3714 that connect the
inner area 3720 to an area outside of the support member 3702. When
the spinal implant 3700 is in the second configuration, a portion
of the proximal retention member 3710 and a portion of the distal
retention member 3712 extend through the openings 3714 to an area
outside of the support member 3702.
[0301] In the illustrated embodiment, the proximal retention member
3710 and the distal retention member 3712 each include a first end
portion 3746 and a second end portion 3744. The first end portions
3746 of the proximal retention member 3710 and the distal retention
member 3712 are coupled by a connecting member 3782 that has a
longitudinal axis L1 (shown in FIG. 74). In some embodiments, the
connecting member 3782, the proximal retention member 3710 and the
distal retention member 3712 are separate components that are
coupled together to form the illustrated structure. In other
embodiments, the connecting member 3782, the proximal retention
member 3710 and the distal retention member 3712 are monolithically
formed.
[0302] The connecting member 3782 defines a longitudinal axis L1,
about which it rotates. As illustrated, as the connecting member
3782 rotates, the proximal retention member 3710 and the distal
retention member 3712 also rotate, thereby causing the end portions
3744 of the proximal retention member 3710 and the distal retention
member 3712 to extend outwardly through the openings 3714. In this
manner, the retention member 3210 can be repeatedly transitioned
between the first configuration and the second configuration.
[0303] In some embodiments, the connecting member 3782 is rotated
using an insertion tool (not shown) that includes a ratchet
mechanism. The insertion tool can rotate the connecting member 3782
in a number of different ways, such as, for example, manually,
pneumatically or electronically.
[0304] As described herein, in some embodiments, the spinal
implants shown and described above can be inserted between adjacent
spinous processes percutaneously using a posterior-lateral
approach. FIGS. 75 and 76 show an implant 8100 and a portion of an
insertion tool 8500 being inserted into a body B using a
posterior-lateral approach according to an embodiment of the
invention. The body B includes spinous processes SP1-SP4, which
define a mid-line axis L.sub.M. A lateral axis L.sub.L is defined
substantially normal to the mid-line axis L.sub.M.
[0305] To position the implant 8100 between adjacent spinous
processes SP2 and SP3, a lateral incision I having a length Y2 is
made a distance X from the mid-line axis L.sub.M. The length Y2 and
the distance X can be selected to allow the implant to be inserted
percutaneously in a minimally-invasive manner. In some embodiments,
the distance X can be, for example, between 25 mm and 100 mm. In
some embodiments, the incision I has a length Y2 that is no greater
than the distance Y1 between the adjacent spinous processes, such
as, for example, SP2 and SP3. In some embodiments, for example, the
length Y2 is no greater than 15 mm and the distance Y1 is between
20 mm and 25 mm. In other embodiments, the length Y2 can exceed the
distance Y1 between the adjacent spinous processes SP2 and SP3. In
some embodiments, for example, the length Y2 can be as much as 50
mm.
[0306] A distraction tool (not shown in FIGS. 75 and 76) is then
inserted through the incision I and is used to define the
passageway P from the incision I to the adjacent spinous processes
SP2 and SP3. The distraction tool can also distract the adjacent
spinous processes SP2 and SP3 to define the desired space between,
as described above. The distraction tool can be any suitable
distraction tool of the type shown and described herein.
[0307] The insertion tool 8500 including the implant 8100 is then
inserted through the incision I and via the passageway P to the
space between the adjacent spinous processes SP2 and SP3. The
implant 8100 is then disposed between the adjacent spinous
processes SP2 and SP3 in any suitable manner, as described above.
For example, in some embodiments, the implant 8100 can include one
or more expandable portions that are adjacent to and/or engage
portions of the spinous processes SP2 and/or SP3 to limit at least
a lateral movement of the implant 8100.
[0308] As shown in FIGS. 75 and 76, during the insertion operation,
the insertion tool 8500 is positioned such that when the implant
8100 is disposed between the adjacent spinous processes SP2 and
SP3, the implant 8100 is substantially aligned with the lateral
axis L.sub.L. Said another way, during insertion, the insertion
tool 8500 is positioned such that the longitudinal axis (not shown)
of the implant 8100 is substantially coaxial with the lateral axis
L.sub.L. As described in more detail herein, the insertion tool
8500 is configured to ensure that the implant 8100 is aligned with
the lateral axis L.sub.L during insertion.
[0309] As shown in FIGS. 77 and 78, the insertion tool 8500, which
can be similar to the insertion tools 1500 and 7500 shown and
described above, includes a curved portion 8520 and an implant
support portion 8530. The insertion tool 8500 defines a center line
CL. As shown in FIGS. 77 and 78, which show a side view and a top
plan view, respectively, of the insertion tool 8500, the center
line CL of the curved portion 8520 defines a radius of curvature R1
about an axis A1 that is substantially normal to the center line
CL. The radius of curvature R1 can be any value suitable to define
and/or proceed along the passageway P such that the implant 8100
and/or a portion of the center line CL is aligned with the lateral
axis L.sub.L during insertion. Moreover, the radius of curvature R1
can be selected to blend with the adjacent portions of the
insertion tool 8500 to ensure that the surface of the insertion
tool 8500 is continuous.
[0310] In some embodiments, for example, an insertion tool 8500 can
have a small radius of curvature R1 (e.g., 20 mm to 50 mm), which
corresponds to a relatively sharp curve. Such an embodiment can be
appropriate, for example, when the distance X between the incision
I and the mid-line axis L.sub.M is relatively small (e.g. 20 mm),
requiring that passageway P have a relatively sharp curve to ensure
that the implant 8100 is properly aligned. In other embodiments,
for example, an insertion tool 8500 can have a large radius of
curvature R1 (e.g., greater than 300 mm), which corresponds to less
curvature. Such an embodiment can be appropriate, for example, when
the distance X between the incision I and the mid-line axis L.sub.M
is relatively great (e.g. greater than 50 mm). In yet other
embodiments, an insertion tool 8500 can have a radius of curvature
R1 that is between 50 mm and 300 mm. In some embodiments, for
example, an insertion tool 8500 can have a radius of approximately
181 mm.
[0311] Although the insertion tool 8500 is shown and described as
having a single radius of curvature R1, in some embodiments, an
insertion tool can have multiple radii of curvature and/or
geometrically complex shapes. For example, FIGS. 79 and 80 show a
side view and a top plan view of an insertion tool 9500 according
to an embodiment of the invention. The insertion tool 9500 includes
a curved portion 9520 and an implant support portion 9530. A center
line CL of the curved portion 9520 defines a first radius of
curvature R1 about a first axis A1 that is substantially normal to
the center line CL. The center line CL of the curved portion 9520
also defines a second radius of curvature R2 about a second axis A2
that is substantially parallel to the first axis A1 and
substantially normal to the center line CL. As described above, the
radii of curvature R1 and R2 can be any value suitable to define
the passageway P such that the implant is aligned with the lateral
axis L.sub.L during insertion. Moreover, as shown in FIG. 79, a
portion of the elongate member 9500 is disposed between the first
axis A1 and the second axis A2. Said another way, the first axis A1
and the second axis A2 are positioned such that the curved portion
9520 forms an "S" shape.
[0312] Although the insertion tool 9500 is shown and described as
defining axis A1 and axis A2 with insertion tool 9500 therebetween,
in other embodiments, an insertion tool can be on the same side of
these axes. Similarly, although the insertion tool 9500 is
described as defining axes A1 and A2 that are substantially
parallel to each other, in other embodiments, an insertion tool can
define axes A1 and A2 that are not substantially parallel to each
other. Said another way, although the insertion tool 9500 is shown
as having a two-dimensional curve, in other embodiments, an
insertion tool can have a three-dimensional curve.
[0313] FIGS. 81-84 are schematic illustrations of an implant 22100
according to an embodiment of the invention. FIGS. 81 and 83 are
posterior views of the implant 22100 in a first configuration and a
second configuration, respectively, disposed between a first
spinous process SP1 and a second spinous process SP2 adjacent the
first spinous process SP1. FIGS. 82 and 84 are lateral views of the
implant 22100 in the first configuration and the second
configuration, respectively, disposed between the first spinous
process SP1 and the second spinous process SP2. The implant 22100
includes a first member 22102 and a second member 22112 movably
coupled to the first member 22102.
[0314] The first member 22102 has a proximal portion 22104, a
distal portion 22106, a first surface 22116, and a second surface
22117. The first surface 22116 of the first member 22102 is
substantially parallel to a longitudinal axis L.sub.A of the first
member 22102. Said another way, the longitudinal axis L.sub.A and a
line defined to include a portion of the first surface 22116 of the
first member 22102 are non-intersecting as they extend to infinity.
Said yet another way, in embodiments in which the first surface
22116 of the first member 22102 includes at least a planar portion,
every point along the longitudinal axis L.sub.A is spaced apart
from the nearest portion of a plane defined to include the planar
portion of the first surface 22116 of the first member 22102 by a
substantially equal distance. The longitudinal axis L.sub.A can,
for example, pass lengthwise (e.g., from the proximal portion 22104
to the distal portion 22106) through the centroid of the first
member 22102 (e.g., the longitudinal axis L.sub.A can be a
centroidal axis of the first member 22102). As shown, when the
implant 22100 is disposed between the first spinous process SP1 and
the second spinous process SP2, the longitudinal axis L.sub.A can
be substantially parallel and/or coincident with a lateral axis
defined by the spinal column.
[0315] As shown, at least a portion of the first surface 22116 of
the first member 22102 is disposed between the first spinous
process SP1 and the second spinous process SP2. In this manner, the
implant 22100 can maintain a minimal spacing between the adjacent
spinous processes SP I and SP2 during extension of the spinal
column (not shown FIGS. 81-84) while allowing flexion of the spinal
column. Moreover, in some embodiments, the implant 22100 can
distract a prior spacing of the adjacent spinous processes SP1 and
SP2.
[0316] The second surface 22117 is disposed at the distal portion
22106 of the first member 22102 and intersects the longitudinal
axis L.sub.A at an angle of approximately 90 degrees. Said another
way, the second surface 22117 of the first member 22102 is
substantially normal to the first surface 22116 of the first member
22102. Although the second surface 22117 of the first member 22102
is shown as intersecting the longitudinal axis L.sub.A of the first
member 22102 at an angle of approximately 90 degrees, in other
embodiments, the second surface of the first member can intersect
the longitudinal axis of the first member by any non-zero
angle.
[0317] The second member 22112 has a first surface 22136 and a
second surface 22137. The first surface 22136 is substantially
parallel to the longitudinal axis L.sub.A of the first member
22102. Said another way, the longitudinal axis L.sub.A and a line
defined to include a portion of the first surface 22136 of the
second member 22112 are non-intersecting as they extend to
infinity. Said yet another way, in embodiments in which the first
surface 22136 of the second member 22112 includes at least a planar
portion, every point along the longitudinal axis L.sub.A is spaced
apart from the nearest portion of a plane defined to include the
planar portion of the first surface 22136 of the second member
22112 by a substantially equal distance. Although the first surface
22136 of the second member 22112 is shown as being substantially
parallel to the longitudinal axis L.sub.A of the first member
22102, in other embodiments, the first surface of the second member
can intersect the longitudinal axis of the first member by any
non-zero angle.
[0318] The second surface 22137 intersects the longitudinal axis
L.sub.A at an angle of approximately 90 degrees. Said another way,
the second surface 22137 of the second member 22112 is
substantially parallel to the second surface 22117 of the first
member 22102, substantially normal to the first surface 22136 of
the second member 22112, and substantially normal to the first
surface 22116 of the first member 22102. Although the second
surface 22137 of the second member 22112 is shown as intersecting
the longitudinal axis L.sub.A of the first member 22102 at an angle
of approximately 90 degrees, in other embodiments, the second
surface of the second member can intersect the longitudinal axis of
the first member by any non-zero angle.
[0319] As shown in FIGS. 81 and 83, the second member 22112 is
coupled to the distal portion 22106 of the first member 22102 such
that at least a portion of the second surface 22137 of the second
member 22112 is in contact with at least a portion of the second
surface 22117 of the first member 22102. In other embodiments,
however, the second member can be coupled to the distal portion of
the first member such that the second surface of the second member
is spaced apart from the second surface of the first member
22102.
[0320] As shown in FIGS. 82 and 84, the first member 22102 has a
first dimension X.sub.1 along an axis X substantially normal to the
longitudinal axis L.sub.A (e.g., a length of the second surface
22117) and a second dimension Y.sub.1 along an axis Y substantially
normal to both the longitudinal axis L.sub.A and the axis X (e.g.,
a height of the second surface 22117). Similarly, the second member
22112 has a first dimension X.sub.2 along the axis X (e.g., a
length of the second surface 22137) and a second dimension Y.sub.2
along the axis Y (e.g., a height of the second surface 22137). The
first dimension X.sub.2 of the second member 22112 is greater than
the second dimension Y.sub.1 of the first member 22102 and is no
greater than the first dimension X.sub.1 of the first member 22102.
The second dimension Y.sub.2 of the second member 22112 is no
greater than the second dimension Y.sub.1 of the first member
22102. Said another way, when the second member 22112 is in a first
position, as shown in FIG. 82, the footprint of the second member
22112 (e.g., a projected area having the first dimension X.sub.2
and the second dimension Y.sub.2) is within the footprint of the
first member 22102 (e.g., a projected area having the first
dimension X.sub.1 and the second dimension Y.sub.1).
[0321] The second member 22112 is coupled to the first member 22102
such that the second member 22112 can rotate relative to the first
member 22102 about an axis of rotation L.sub.R substantially
parallel to the longitudinal axis L.sub.A. As indicated by the
arrows AA in FIGS. 83 and 84, the second member 22112 can rotate
relative to the first member 22102 between a first position (FIGS.
81 and 82) and a second position (FIGS. 83 and 84). When the second
member 22112 is in the first position, the implant 22100 can be
inserted such that at least a portion of the first surface 22116 of
the first member 22102 is disposed between the first spinous
process SP1 and the second spinous process SP2. When the second
member 22112 is in the second position, the second member 22112
limits movement of the first member 22102 in the proximal direction
along the longitudinal axis L.sub.A and relative to the adjacent
spinous processes SP1 and SP2. The second member 22112 can limit
movement of the first member 22102, for example, by contacting
and/or engaging the spinous processes SP1 and SP2 (e.g., either
directly or through surrounding tissue).
[0322] As shown in FIG. 81, when the second member 22112 is in the
first position, the second surface 22137 of the second member 22112
is in contact with and/or adjacent to at least a portion of the
second surface 22117 of the first member 22102. When the second
member 22112 is in the second position, at least a portion 22131 of
the second surface 22137 (indicated by the shaded region in FIG.
84) is spaced apart from the portion of the second surface 22117 of
the first member 22102. In this manner, the portion 22131 of the
second surface 22137 can limit movement of the first member 22102
by contacting and/or engaging the spinous processes SP1 and/or SP2
(e.g., either directly or through surrounding tissue). Although the
second surface 22137 of the second member 22112 is shown in FIG. 81
as being in continuous contact with at least a portion of the
second surface 22117 of the first member 22102, it is understood
that portions of the second surface 22137 of the second member
22112 can be spaced apart from the second surface 22117 of the
first member 22102. For example, in some embodiments, portions of
the second surface 22137 of the second member 22112 can be spaced
apart from the second surface 22117 of the first member 22102 as a
result of surface roughness, corrugation and/or waviness of the
second surface 22137 of the second member 22112 and/or the second
surface 22117 of the first member 22102.
[0323] Similarly stated, when the second member 22112 is in the
first position, a cross-sectional area A.sub.2 bounded by an outer
surface of the second member 22112 (e.g., the area bounded by the
second surface 22137) is within a cross-sectional area A.sub.1
bounded by an outer surface of the first member 22102 (e.g., the
area bounded by the second surface 22117) when the areas A.sub.1
and A.sub.2 are projected on a plane substantially normal to the
longitudinal axis L.sub.A (see FIG. 82). When the second member
22112 is in the second position, a portion of the cross-sectional
area A.sub.2 bounded by the outer surface of the second member
22112 (e.g., the area bounded by the portion 22131 of the second
surface 22137) is outside of the cross-sectional area A.sub.1
bounded by an outer surface of the first member 22102 when the
areas A.sub.1 and A.sub.2 are projected on a plane substantially
normal to the longitudinal axis L.sub.A (see FIG. 84).
[0324] Said another way, when the second member 22112 is in the
first position, the first dimension X.sub.2 of the second member
22112 is aligned with (e.g., is substantially parallel to) the
first dimension X.sub.1 of the first member 22102. Because the
first dimension X.sub.2 of the second member 22112 is no greater
than the first dimension X.sub.1 of the first member 22102 and the
second dimension Y.sub.2 of the second member 22112 is no greater
than the second dimension Y.sub.1 of the first member 22102, when
the second member 22112 is in the first position, the footprint of
the second member 22112 (e.g., the shape of a portion of the second
member 22112, such as for example, the shape corresponding to the
area A.sub.2 bounded by the outer surface of the second member
22112) is within the footprint of the first member 22102 (e.g., the
shape of a portion of the first member 22102, such as for example,
the shape corresponding to the area A.sub.1 bounded by the outer
surface of the first member (22102).
[0325] When the second member 22112 is in the second position, the
second dimension Y.sub.2 of the second member 22112 is aligned with
the first dimension X.sub.1 of the first member 22102 (i.e., the
second member 22112 is rotated approximately 90 degrees relative to
the first member 22102). Because the first dimension X.sub.2 of the
second member 22112 is greater than the second dimension Y.sub.1 of
the first member 22102, a portion of the footprint of the second
member 22112 is disposed outside of the footprint of the first
member 22102. In this manner, when the second member 22112 is in
the first position, the implant 22100 can be inserted between the
spinous processes SP1 and SP2 unimpeded by the second member 22112
(i.e., the second member 22112 does not limit movement of the first
member 22102 relative to the spinous processes SP1 and SP2).
Conversely, when the second member 22112 is in the second position,
a portion of the second member 22112 can contact and/or engage the
first spinous process SP1 and/or the second spinous process SP2 to
limit longitudinal movement of the first member 22102 relative to
the spinous processes SP1 and SP2.
[0326] In use, the adjacent spinous processes SP1 and SP2 can be
distracted prior to inserting the implant 22100 into the patient.
An access passageway can then be defined to allow insertion of the
implant 22100. The passageway can have any suitable shape (e.g.,
curved in two dimensions, curved in multiple planes or the like)
and can be formed by any suitable method and by any suitable tool,
as discussed herein. After the access passageway is defined, the
implant 22100 is inserted percutaneously and advanced along the
longitudinal axis L.sub.A until it is positioned between the
spinous processes SP1 and SP2. The implant 22100 is inserted with
the second member 22112 first and in the first position. Once the
implant 22100 is in place, the second member 22112 is moved to the
second position to limit lateral movement of the first member 22102
in the proximal direction the longitudinal axis L.sub.A and
relative to the spinous processes SP1 and SP2.
[0327] If or when it is desirable to change the position of the
implant 22100 and/or remove the implant 22100, the second member
22112 can be moved back to the first position, thereby allowing the
first member 22102 to be moved laterally. Once the first member
22102 is repositioned as desired, the second member 22112 can be
moved back to the second position, if desired.
[0328] Although the axis of rotation L.sub.R is shown as being
coincident with the longitudinal axis L.sub.A, in other
embodiments, the axis of rotation L.sub.R can be offset from and
parallel to the longitudinal axis L.sub.A. In other embodiments,
the axis of rotation L.sub.R can be angularly offset from the
longitudinal axis L.sub.A (i.e., the axis of rotation L.sub.R and
the longitudinal axis L.sub.A intersect). Similarly, although the
second member 22112 is shown and described as being rotatably
coupled to the first member 22102, in other embodiments, the second
member 22112 can movably coupled to the first member 22102 such
that the second member 22112 translates relative to the first
member 22102 between the first position and the second
position.
[0329] Although the first dimension X.sub.2 of the second member
22112 is shown in FIG. 82 as being less than the first dimension
X.sub.1 of the first member 22102, in some embodiments the first
dimension X.sub.2 of the second member 22112 can be substantially
equal to the first dimension X.sub.1 of the first member 22102.
Similarly, although the second dimension Y.sub.2 of the second
member 22112 is shown in FIG. 82 as being less than the second
dimension Y.sub.1 of the first member 22102, in some embodiments
the second dimension Y.sub.2 of the second member 22112 can be
substantially equal to the second dimension Y.sub.1 of the first
member 22102. In this manner, the first surface 22116 of the first
member 22102 and the first surface 22136 of the second member 22112
can collectively form a continuous surface.
[0330] Although a portion 22131 of the second surface 22137 of the
second member 22112 is shown and described as being in contact with
at least a portion of the second surface 22117 of the first member
22102 when the second member 22112 is in the first position, in
other embodiments the entire second surface 22137 of the second
member 22112 can be spaced apart from the second surface 22117 of
the first member 22102 when the second member 22112 is in the first
position. For example, in some embodiments, the second surface of
the second member can be complementarily disposed adjacent at least
a portion of the second surface of the first member when the second
member is in the first position. The second surface of the second
member can be disposed apart from (e.g., out of alignment with) the
portion of the second surface of the first member when the second
member is in the second position. In this manner the first member
and the second member can be spaced apart to allow the second
member to move relative to the first member without touching the
first member.
[0331] Although a portion 22131 of the second surface 22137 of the
second member 22112 is shown and described as being spaced apart
from the second surface 22117 of the first member 22102 when the
second member 22112 is in the second position, in other embodiments
the entire second surface 22137 of the second member 22112 can
remain in contact with the second surface 22117 of the first member
22102 when the second member 22112 is in the second position. For
example, FIGS. 85-90 are schematic illustrations of an implant
22200 according to an embodiment of the invention. FIGS. 85 and 88
are posterior views of the implant 22200 in a first configuration
and a second configuration, respectively, disposed between a first
spinous process SP1 and a second spinous process SP2 adjacent the
first spinous process SP1. FIGS. 86 and 89 are side views of the
implant 22200 in the first configuration and the second
configuration, respectively disposed between the spinous processes
SP1 and SP2. FIGS. 87 and 90 are cross-sectional views of the
implant 22200 taken along lines A-A in FIGS. 86 and 89,
respectively.
[0332] The implant 22200 includes a first member 22202 and a second
member 22212 movably coupled to the first member 22202. The first
member 22202 has a proximal portion 22204, a distal portion 22206,
a first surface 22216, and a second surface 22217. The first
surface 22216 of the first member 22202 is substantially parallel
to a longitudinal axis L.sub.A of the first member 22202. Said
another way, the longitudinal axis L.sub.A and a line defined to
include a portion of the first surface 22216 of the first member
22202 are non-intersecting as they extend to infinity. Said yet
another way, in embodiments in which the first surface 22216 of the
first member 22202 includes at least a planar portion, every point
along the longitudinal axis L.sub.A is spaced apart from the
nearest portion of a plane defined to include the planar portion of
the first surface 22216 of the first member 22202 by a
substantially equal distance. The longitudinal axis L.sub.A can,
for example, pass lengthwise (e.g., from the proximal portion 22204
to the distal portion 22206) through the centroid of the first
member 22202. As shown, when the implant 22200 is disposed between
the first spinous process SP1 and the second spinous process SP2,
the longitudinal axis L.sub.A can be substantially parallel and/or
coincident with a lateral axis defined by the spinal column.
[0333] As shown, at least a portion of the first surface 22216 of
the first member 22202 is disposed between the first spinous
process SP1 and the second spinous process SP2. In this manner, the
implant 22200 can maintain a minimal spacing between the adjacent
spinous processes SP1 and SP2 during extension of the spinal column
(not shown FIGS. 81-84) while allowing flexion of the spinal
column.
[0334] The second surface 22217 is disposed at the distal portion
22206 of the first member 22202 and intersect the longitudinal axis
L.sub.A at an angle of approximately 90 degrees. Said another way,
the second surface 22217 of the first member 22202 is substantially
normal to the first surface 22216 of the first member 22202.
[0335] The second member 22212 has a first surface 22236, a second
surface 22237 and a saddle surface 22251. The first surface 22236
is substantially parallel to the longitudinal axis L.sub.A of the
first member 22202. Said another way, the longitudinal axis L.sub.A
and a line defined to include a portion of the first surface 22236
of the second member 22212 are non-intersecting as they extend to
infinity. Said yet another way, in embodiments in which the first
surface 22236 of the second member 22212 includes at least a planar
portion, every point along the longitudinal axis L.sub.A is spaced
apart from the nearest portion of a plane defined to include the
planar portion of the first surface 22236 of the second member
22212 by a substantially equal distance. The second surface 22237
intersects the longitudinal axis L.sub.A at an angle of
approximately 90 degrees. Said another way, the second surface
22237 of the second member 22212 is substantially parallel to the
second surface 22217 of the first member 22202, substantially
normal to the first surface 22236 of the second member 22212, and
substantially normal to the first surface 22216 of the first member
22202. The saddle surface 22251 is adjacent the second surface
22237 and has a curved shape that can form a portion of a saddle
22252, as discussed in more detail herein.
[0336] The second member 22212 is coupled to the distal portion
22206 of the first member 22202 such that the second surface 22237
of the second member 22212 is in contact with a portion of the
second surface 22217 of the first member 22202. The second member
22212 is rotatably coupled to the first member 22202 about an axis
of rotation L.sub.R substantially parallel to and offset from the
longitudinal axis L.sub.A. As indicated by the arrows BB in FIGS.
88-90, the second member 22212 can rotate relative to the first
member 22202 between a first position (FIGS. 85-87) and a second
position (FIGS. 88-90).
[0337] As shown in FIGS. 85-87, when the second member 22212 is in
the first position, a cross-sectional area A.sub.2 bounded by an
outer surface of the second member 22212 (i.e., the cross-sectional
area of the second member 22212 taken along line A-A in FIG. 86) is
within a cross-sectional area A.sub.1 bounded by an outer surface
of the first member 22202 (i.e., the area of the second surface
22217) when projected on a plane substantially normal to the
longitudinal axis L.sub.A (see FIG. 87). As shown in FIGS. 88-90,
when the second member 22212 is in the second position, a portion
of the cross-sectional area A.sub.2 of the second member 22212 is
outside of the cross-sectional area A.sub.1 of the first member
22202 when the areas A.sub.1 and A.sub.2 are projected on a plane
substantially normal to the longitudinal axis L.sub.A (see FIG.
90). As shown in FIG. 86, the cross-sectional area A.sub.2 of the
second member 22212 need not coincide with the second surface 22237
of the second member 22212, but rather can be considered at any
longitudinal location along the second member 22212 (e.g., at the
widest point of the second member 22212). Similarly, although the
cross-sectional area A.sub.1 of the first member 22202 is shown as
being the area of the second surface 22217, in other embodiments,
the cross-sectional area A.sub.1 of the first member 22202 can be
considered at any longitudinal location along the first member
22202.
[0338] As shown in FIG. 88, when the second member 22212 is in the
second position, the first surface 22216 of the first member 22202
and the saddle surface 22251 of the second member 22212
collectively form a portion of a saddle 22252 configured to receive
a portion of the spinous process SP1. In this manner, the saddle
22252 can receive and/or engage a portion of the spinous process
SP1 and/or its surrounding tissue to limit movement of the first
member 22202 along the longitudinal axis L.sub.A and relative to
the spinous processes SP1 and SP2. In some embodiments, the saddle
22252 and/or the saddle surface 22251 can have a curved surface
that substantially corresponds to a shape and/or a size of the
spinous process SP1 (e.g., the spinous process SP1 and/or the
surrounding tissue). In some embodiments, the shape and/or size of
the saddle surface 22251 can be configured to more evenly
distribute forces between the saddle 22252 and the spinous process
SP1. In some embodiments, the saddle surface 22251 and the first
surface 22216 of the first member 22202 can form a substantially
smooth and/or continuous surface.
[0339] Returning to FIGS. 81-84, although the first surface 22116
of the first member 22102 and the first surface 22136 of the second
member 22112 are shown and described as being substantially
parallel to the longitudinal axis L.sub.A, the first surface 22116
of the first member 22102 and/or the first surface 22136 of the
second member 22112 can have any suitable shape, contour and/or
orientation. For example, in some embodiments, the first surface
22116 of the first member 22102 can have a curved shape to form a
portion of a saddle, as described above. In other embodiments, a
first surface of a first member can be tapered. For example, FIGS.
91-94 are schematic illustrations of an implant 22300 according to
an embodiment of the invention. FIGS. 91 and 93 are posterior views
of the implant 22300 in a first configuration and a second
configuration, respectively, disposed between a first spinous
process SP1 and a second spinous process SP2. FIGS. 92 and 94 are
side views of the implant 22300 in the first configuration and the
second configuration, respectively, disposed between the spinous
processes SP1 and SP2.
[0340] The implant 22300 includes a first member 22302 and a second
member 22312 movably coupled to the first member 22302. The first
member 22302 has a proximal portion 22304, a distal portion 22306,
a first surface 22316, and a second surface 22317. The first
surface 22316 of the first member 22302 is tapered in a direction
substantially parallel to a longitudinal axis L.sub.A of the first
member 22302 such that a size Y.sub.3 of the distal portion 22306
is less than a size Y.sub.4 of the proximal portion 22304. In this
manner, when a portion of the first surface 22316 of the first
member 22202 is disposed between the first spinous process SP1 and
the second spinous process SP2, the tapered of the first member
22302 can contact and/or engage the spinous process SP1 (either
directly or indirectly through its surrounding tissue) to limit
movement of the first member 22302 along the longitudinal axis
L.sub.A and relative to the adjacent spinous processes SP1 and
SP2.
[0341] The distal portion 22306 of the first member 22302 includes
the second surface 22317, which intersects the longitudinal axis
L.sub.A at an acute angle .THETA.. Said another way, the second
surface 22317 of the first member 22302 is angularly offset from
the longitudinal axis L.sub.A by an angle greater than zero degrees
and less than 90 degrees.
[0342] The second member 22312 has a first surface 22336 and a
second surface 22337. The first surface 22336 is substantially
parallel to the longitudinal axis L.sub.A of the first member
22302. Said another way, the longitudinal axis L.sub.A and a line
defined to include a portion of the first surface 22336 of the
second member 22112 are non-intersecting as they extend to
infinity. Said yet another way, in embodiments in which the first
surface 22336 of the second member 22312 includes at least a planar
portion, every point along the longitudinal axis L.sub.A is spaced
apart from the nearest portion of a plane defined to include the
planar portion of the first surface 22136 of the second member
22112 by a substantially equal distance. The second surface 22337
intersects the longitudinal axis L.sub.A at the acute angle
.THETA.. Said another way, the second surface 22237 of the second
member 22212 is substantially parallel to the second surface 22217
of the first member 22202.
[0343] As described above, the second member 22312 is rotatably
coupled to the distal portion 22306 of the first member 22302 about
an axis of rotation L.sub.R such that the second member 22312 can
rotate relative to the first member 22302 between a first position
(FIGS. 91 and 92) and a second position (FIGS. 93 and 94). When the
second member 22312 is in the first position, the second surface
22337 of the second member 22312 is in contact with at least a
portion of the second surface 22317 of the first member 22302. When
the second member 22312 is in the second position, at least a
portion of the second surface 22337 is spaced apart from the
portion of the second surface 22317 of the first member 22302. In
this manner, the portion of the second surface 22337 can limit
movement of the first member 22302 by contacting and/or engaging
the spinous process SP2 (either directly or indirectly through its
surrounding tissue).
[0344] Although the first member 22302 is shown as being
asymmetrically tapered along the longitudinal axis L.sub.A (i.e.,
tapered on the first surface 22316 without being tapered on at
least one other surface), in some embodiments, the first member
22302 can be symmetrically tapered along the longitudinal axis
L.sub.A. In other embodiments, the first member 22302 can be
tapered along the longitudinal axis L.sub.A in two dimensions
(i.e., a height and a width).
[0345] FIGS. 95-99 show an implant 22400 according to an embodiment
of the invention. FIGS. 95 and 96 are perspective views of the
implant 22400 in a first configuration and a second configuration,
respectively. FIGS. 97-99 are perspective views of portions of the
implant 22400. The implant 22400 includes a support member 22402, a
proximal retention member 22410 and a distal retention member
22412.
[0346] The support member 22402 has a proximal portion 22404, a
distal portion 22406 and a support surface 22416. The support
surface 22416 is configured to be disposed between adjacent spinous
processes (not shown in FIGS. 95-99) to maintain a minimal spacing
between the spinous processes during extension of the spinal
column. Accordingly, the support member 22402 can be constructed
from any biocompatible material having sufficient strength, such
as, for example, stainless steel, plastic, polyetheretherketone
(PEEK), carbon fiber, ultra-high molecular weight (UHMW)
polyethylene, and the like.
[0347] The proximal portion 22404 of the support member 22402
includes a proximal end surface 22418 substantially normal to the
support surface 22416 of the support member 22402. Similarly, the
distal portion 22406 of the support member 22402 includes a distal
end surface 22417 substantially normal to the support surface 22416
of the support member 22402. As shown in FIG. 97, the proximal end
surface 22418 includes a protrusion 22414 and defines a first
opening 22409 that extends through the support member 22402 and
receives a pivot rod 22470, as described in more detail herein. The
distal end surface 22417 defines a second opening 22408 (shown in
hidden lines) that receives a portion of a locking member 22454 and
a biasing member 22458, as described in more detail herein.
[0348] As shown in FIG. 99, the proximal retention member 22410
includes a retention surface 22447 that is substantially parallel
to the proximal end surface 22418 of the support member 22402. The
retention surface 22447 of the proximal retention member 22410
defines a first opening 22448 and a second opening 22449. The first
opening 22448 receives the proximal end portion 22471 of the pivot
rod 22470. The second opening 22449 has an arcuate shape and
receives a portion of the protrusion 22414 of the support member
22402. In this manner, as described in more detail herein, when the
proximal retention member 22410 rotates relative to the support
member 22402, the protrusion 22414 moves within second opening
22449 to limit end positions of the rotation of the proximal
retention member 22410 relative to the support member 22402.
[0349] Similarly, as shown in FIG. 98, the distal retention member
22412 includes an outer surface 22436 and a retention surface
22437. The outer surface 22436 of the distal retention member 22412
has a curved shape to facilitate insertion of the implant 22400
into the body. For example, in some embodiments, the outer surface
22436 of the distal retention member 22412 can be configured to
displace a bodily tissue, dilate a bodily tissue and/or distract a
space between adjacent spinous processes. The outer surface 22436
of the distal retention member 22412 also defines two recesses
22439, one of which receives an end portion 22457 of the locking
member 22454 when the implant 22400 is in the second configuration
(see FIG. 96).
[0350] The retention surface 22437 of the distal retention member
22412 is substantially parallel to the distal end surface 22417 of
the support member 22402. The retention surface 22437 of the distal
retention member 22412 defines a recess 22438 that receives the end
portion 22457 of the locking member 22454.
[0351] The proximal retention member 22410 and the distal retention
member 22412 are rotatably coupled to the support member 22402 by
the pivot rod 22470. As shown in FIG. 98, a distal end portion
22472 of the pivot rod 22470 is affixed to the retention surface
22437 of the distal retention member 22412. In some embodiments,
for example, the distal end portion 22472 of the pivot rod 22470
can be affixed to the retention surface 22437 by disposing a
portion of the distal end portion 22472 of the pivot rod 22470
within an opening (not shown in FIG. 98) defined by the retention
surface 22437. In such embodiments, the opening and the distal end
portion 22472 of the pivot rod 22470 can be configured to produce
an interference fit. Similarly, in such embodiments, the distal end
portion 22472 of the pivot rod 22470 can be welded to the retention
surface 22437.
[0352] The pivot rod 22470 extends through the first opening 22409
of the support member 22402 such that the proximal end portion
22471 of the pivot rod 22470 is received within the first opening
22448 of the proximal retention member 22410 and is fixedly coupled
to the proximal retention member 22410. In this manner, the
proximal retention member 22410 and the distal retention member
22412 are coupled together and can collectively rotate relative to
the support member 22402 about an axis of rotation L.sub.R (which
is coincides with the center line of the pivot rod 22470), as
indicated by the arrows CC in FIG. 96.
[0353] The proximal retention member 22410 and the distal retention
member 22412 can collectively rotate relative to the support member
22402 between a first position (i.e., the first configuration of
the implant 22400, as shown in FIG. 95) and a second position
(i.e., the second configuration of the implant 22400, as shown in
FIG. 96). When the proximal retention member 22410 and the distal
retention member 22412 are in the first position, the retention
surface 22447 of the proximal retention member 22410 is in contact
with and/or adjacent to the proximal end surface 22418 of the
support member 22402 and the retention surface 22437 of the distal
retention member 22412 is in contact with and/or adjacent to the
distal end surface 22417 of the support member 22402. In this
manner, the implant 22400 can be inserted between adjacent spinous
processes unimpeded by the proximal retention member 22410 and/or
the distal retention member 22412 (i.e., the proximal retention
member 22410 and/or the distal retention member 22412 do not limit
movement of the support member 22402 relative to the spinous
processes). As described above, it is understood that portions of
the retention surface 22447 and the retention surface 22437 can be
spaced apart from the proximal end surface 22418 and the distal end
surface 22417, respectively. For example, in some embodiments,
portions of the retention surface 22447 and/or the retention
surface 22437 of the second member 22412 can be spaced apart from
the proximal end surface 22418 and/or the distal end surface 22417,
respectively, as a result of surface roughness, corrugation and/or
waviness of the mating surfaces.
[0354] Similarly stated, when the proximal retention member 22410
and the distal retention member 22412 are in the first position,
the area A.sub.2 of the proximal retention surface 22447 is within
the area A.sub.1 of the proximal end surface 22418 of the support
member 22402 when the areas A.sub.1 and A.sub.2 are projected on a
plane substantially parallel to the proximal end surface 22418 of
the support member 22402. Similarly, the area A.sub.4 of the distal
retention surface 22437 is within the area A.sub.3 of the distal
end surface 22417 of the support member 22402 when the areas
A.sub.3 and A.sub.4 are projected on a plane substantially parallel
to the distal end surface 22417 of the support member 22402.
[0355] Moreover, when the implant 22400 is in the first
configuration, the biasing member 22458 exerts a force against the
locking member 22454 such that the end portion 22457 of the locking
member 22454 is disposed outside of the support member 22402 and is
received within the recess 22438 of the retention surface 22437 of
the distal retention member 22412. Accordingly, when the implant
22400 is in the first configuration, the locking member 22454
temporarily maintains the distal retention member 22412 and the
proximal retention member 22410 in the first position. The recess
22438 of the retention surface 22437 has a curved shape that
substantially corresponds to a shape of the end portion 22457 of
the locking member 22454. When a rotational force is applied to the
proximal retention member 22410 and/or the distal retention member
22412, as shown by the arrow CC in FIG. 96, a resulting force is
produced that moves the end portion 22457 of the locking member
22454 into the opening 22408 of the support member 22402. In this
manner, the implant 22400 can be moved into the second
configuration when disposed between adjacent spinous processes.
Although the locking member 22454 is shown as being a cylindrical
pin, in other embodiments, any suitable detent can used to maintain
the implant 22400 in the first configuration.
[0356] When the proximal retention member 22410 and the distal
retention member 22412 are in the second position, at least a
portion of the proximal retention surface 22447 and at least a
portion of the distal retention surface 22437 are spaced apart from
the proximal end surface 22418 of the support member 22402 and the
distal end surface 22417 of the support member 22402, respectively.
In this manner, when implant 22400 is in the second configuration,
the portion of the proximal retention surface 22447 and/or the
portion of the distal retention surface 22437 can contact and/or
engage the spinous processes to limit lateral movement of the
support member 22402 relative to the spinous processes.
[0357] When the proximal retention member 22410 and the distal
retention member 22412 are in the second position, a portion of the
area A.sub.2 of the proximal retention surface 22447 is outside of
the area A.sub.1 of the proximal end surface 22418 of the support
member 22402 when projected on a plane substantially parallel to
the proximal end surface 22418 of the support member 22402.
Similarly, a portion of the area A.sub.4 of the distal retention
surface 22437 is outside of the area A.sub.3 of the distal end
surface 22417 of the support member 22402 when projected on a plane
substantially parallel to the distal end surface 22417 of the
support member 22402.
[0358] Moreover, when the implant 22400 is in the second
configuration, the biasing member 22458 exerts a force against the
locking member 22454 such that the end portion 22457 of the locking
member 22454 is received, at least partially, within one of the
recesses 22439 of the outer surface 22436 of the distal retention
member 22412. Accordingly, when the implant 22400 is in the second
configuration, the locking member 22454 maintains the distal
retention member 22412 and the proximal retention member 22410 in
the second position. The recesses 22439 of the outer surface 22437
are configured to receive, at least partially, the end portion
22457 of the locking member 22454 such that the distal retention
member 22412 and the proximal retention member 22410 are releasably
locked in the second position. In this manner, in some embodiments,
a deployment tool, of the types shown and described herein, is used
to move the locking member 22454 into the opening 22408 of the
support member 22402 so that the implant 22400 can be moved from
the second configuration to the first configuration. The locking
member 22454 is retained within the second opening 24408 by the
retainer 22458. The retainer 22458 can be coupled within the
opening 24408, for example, by an interference fit, a weld, a
swaged fit or the like.
[0359] Moreover, when the implant 22400 is in the second
configuration, the protrusion 22414 of the proximal end surface
22418 can be in contact with the retention surface 22447 of the
proximal retention member 22410 that defines an end portion of the
arcuate opening 22449. In this manner, the proximal retention
member 22410 is prevented from being rotated more than
approximately 90 degrees from the first position. Said another way,
the protrusion 22414 and the surfaces defining the arcuate opening
22449 limit the rotation of the proximal retention member 22410
relative to the support member 22402.
[0360] Although the locking member 22454 is shown as being disposed
within the support member 22402 such that an end portion 22457 of
the locking member 22454 is received within the recesses 22438
and/or 22439, in other embodiments, a locking member can be
disposed within a proximal retention member and/or a distal
retention member such that an end portion of the locking member is
received within a recess in the proximal end surface of the support
member and/or the distal end surface of the support member to
temporarily maintain the implant in a first and/or a second
configuration. In other embodiments, a locking member can be
coupled to an outer surface of the support member such that a
portion of the locking member is received within recesses defined
by an outer surface of a proximal retention member and/or a distal
retention member. In yet other embodiments, an implant can include
a first locking member or detent to temporarily maintain the
implant in a first configuration and a second locking member or
detent to temporarily maintain the implant in a second
configuration.
[0361] Although the proximal retention member 22410 and the distal
retention member 22412 are shown and described as being disposed
adjacent the proximal end surface 22417 and the distal end surface
22418 of the support member 22402, in other embodiments, an implant
can include a retention member disposed at a location other than at
a proximal end surface or a distal end surface. For example, in
some embodiments, an implant can include a retention member
disposed in a central portion of a support member. In some
embodiments, a retention member can be movably coupled to a support
member such that the retention member is disposed within the
support member when the retention member is in a first position and
at least a portion of the retention member is disposed outside of
the support member when the retention member is in a second
position.
[0362] FIGS. 100-105 show an implant 22500 according to an
embodiment of the invention. FIGS. 100-102 show a perspective view,
a front view and a bottom view, respectively, of the implant 22500
in a first configuration. FIGS. 103-105 show a perspective view, a
front view and a bottom view, respectively, of the implant 22500 in
a second configuration. The implant 22500 includes a support member
22502, a proximal retention member 22510 and a distal retention
member 22512.
[0363] The support member 22502 has a proximal portion 22504, a
distal portion 22506 and a support surface 22516. The support
surface 22516 is configured to be disposed between adjacent spinous
processes (not shown in FIGS. 100-105) to maintain a minimal
spacing between the spinous processes during extension of the
spinal column. The support surface 22516 defines a recess 22549
having two shoulder surfaces 22560. As described in more detail
herein, the shoulder surfaces 22560 are configured to engage a
protrusion 22514 of the proximal retention member 22510 to limit
the end positions of the rotation of the proximal retention member
22510 relative to the support member 22502.
[0364] The proximal portion 22504 of the support member 22502
includes a proximal end surface 22518 substantially normal to the
support surface 22516 of the support member 22502. Similarly, the
distal portion 22506 of the support member 22502 includes a distal
end surface 22517 substantially normal to the support surface 22516
of the support member 22502. As shown in FIGS. 107 and 110, the
proximal end surface 22518 defines a first opening 22509 that
extends through the support member 22502 and receives a pivot rod
22570. As shown in FIGS. 107 and 110, the distal end surface 22517
defines a second opening 22508 that receives a portion of a locking
member 22554 and a biasing member 22558, as described in more
detail herein.
[0365] The proximal retention member 22510 includes an outer
surface 22546, a proximal end surface 22561 and retention surface
22547. The outer surface 22546 has a curved surface that
substantially corresponds to a shape and/or a size of the support
surface 22516 of the support member 22502. In this manner, the
outer surface 22546 of the proximal retention member 22510 and the
support surface 22516 of the support member 22502 can form a
substantially smooth and/or continuous surface when the implant
22500 is in the first configuration.
[0366] As shown in FIGS. 107-109, the proximal end surface 22561 of
the proximal retention member 22510 is configured to be received
within a receiving area 22642 of a deployment tool 22600. The
proximal end surface 22561 defines a threaded opening 22580
configured engage a threaded portion 22672 of a rod 22670 of the
deployment tool 22600.
[0367] The retention surface 22547 of the proximal retention member
22510 is substantially parallel to the proximal end surface 22518
of the support member 22502. The retention surface 22547 of the
proximal retention member 22510 defines an opening 22548 and a
protrusion 22514. As shown in FIGS. 107 and 110, the opening 22548
receives the proximal end portion 22471 of the pivot rod 22570. The
outer surface 22546 also defines an opening 25584. The opening
25584 can be used, for example, during the assembly of the implant
22500 to ensure that the proximal end portion 22471 of the pivot
rod 22570 is properly positioned and/or affixed within the opening
22509. In some embodiments, the opening 22584 can be welded
closed.
[0368] The protrusion 22514 of the proximal retention member 22510
is received within the recess 22549 defined by the support surface
22516. When the proximal retention member 22510 rotates relative to
the support portion 22502, the protrusion 22514 contacts the
shoulder surfaces 22560 (see e.g., FIGS. 104 and 105) to limit the
end positions of the rotation of the proximal retention member
22510 relative to the support member 22502.
[0369] Similarly, the distal retention member 22512 includes an
outer surface 22536 and a retention surface 22537. The outer
surface 22536 of the distal retention member 22512 has a curved
shape (e.g., a tapered end portion) and includes a tip 22535 to
facilitate insertion of the implant 22500 into the body. In some
embodiments, for example, the outer surface 22436 and/or the tip
22535 can displace a bodily tissue when the implant 22500 is
inserted into the body. In some embodiments, the outer surface
22436 and/or the tip 22535 can dilate a bodily tissue, such as the
supraspinous ligament, when the implant 22500 is inserted into the
body. In some embodiments, the outer surface 22436 and/or the tip
22535 can distract a space between adjacent spinous processes when
the implant 22500 is inserted into the body.
[0370] The shape of the outer surface 22536 of the distal retention
member 22512 is asymmetrical such that when the implant 22500 is in
the second configuration, a portion of the support surface 22516 of
the support member 22502 and a portion of the outer surface 22536
of the distal retention member 22512 form a substantially
continuous and/or linear surface (see e.g., FIG. 105). In this
manner, when the implant 22500 is in the second configuration, the
substantially continuous and/or linear surface formed by the
support surface 22516 of the support member 22502 and the outer
surface 22536 of the distal retention member 22512 can limit
rotational movement of the implant 22500 about an axis normal to
the axis L.sub.R (e.g., in a direction as indicated by the arrow JJ
in FIG. 105). Said another way, the substantially continuous and/or
linear surface formed by the support surface 22516 of the support
member 22502 and the outer surface 22536 of the distal retention
member 22512 can prevent the implant 22500 from rotating out of its
position between the adjacent spinous processes.
[0371] The outer surface 22536 of the distal retention member 22512
defines two recesses 22539, one of which receives an end portion
22557 of the locking member 22454 when the implant 22500 is in the
second configuration (see FIG. 103). The outer surface 22536 of the
distal retention member 22512 also defines a threaded opening 22582
configured engage the threaded portion 22672 of a rod 22670 of the
deployment tool 22600.
[0372] The retention surface 22537 of the distal retention member
22512 is substantially parallel to the distal end surface 22517 of
the support member 22502. The retention surface 22537 of the distal
retention member 22512 defines a recess 22538 that receives the end
portion 22557 of the locking member 22554.
[0373] The proximal retention member 22510 and the distal retention
member 22512 are rotatably coupled to the support member 22502 by
the pivot rod 22570, as described above. As shown in FIG. 107, the
pivot rod 22570 extends through the first opening 22509 of the
support member 22502 such that the proximal end portion 22571 of
the pivot rod 22570 is received within the first opening 22548 of
the proximal retention member 25510 and is fixedly coupled to the
proximal retention member 22510. In this manner, the proximal
retention member 22510 and the distal retention member 22512 are
coupled together and can collectively rotate relative to the
support member 22502 about an axis of rotation L.sub.R (which is
coincides with the center line of the pivot rod 22570), as
indicated by the arrows KK in FIG. 105.
[0374] The proximal retention member 22510 and the distal retention
member 22512 can collectively rotate relative to the support member
22502 between a first position (i.e., the first configuration of
the implant 22500, as shown in FIGS. 100-102) and a second position
(i.e., the second configuration of the implant 22500, as shown in
FIG. 103-105). When the implant 22500 is in the first
configuration, the retention surface 22547 of the proximal
retention member 22510 is in contact with and/or adjacent to the
proximal end surface 22518 of the support member 22502 and the
retention surface 22537 of the distal retention member 22512 is in
contact with and/or adjacent to the distal end surface 22517 of the
support member 22502. In this manner, the implant 22500 can be
inserted between adjacent spinous processes unimpeded by the
proximal retention member 22510 and/or the distal retention member
22512 (i.e., the proximal retention member 22510 and/or the distal
retention member 22512 do not limit movement of the support member
22502 relative to the spinous processes). As described above, it is
understood that portions of the retention surface 22547 and the
retention surface 22537 can be spaced apart from the proximal end
surface 22518 and the distal end surface 22517, respectively. For
example, in some embodiments, portions of the retention surface
22547 and/or the retention surface 22537 of the second member 22512
can be spaced apart from the proximal end surface 22518 and/or the
distal end surface 22517, respectively, as a result of surface
roughness, corrugation and/or waviness of the mating surfaces.
[0375] Similarly stated, when the implant 22500 is in the first
configuration, the area A.sub.2 of the proximal retention surface
22547 is within the area A.sub.1 of the proximal end surface 22518
of the support member 22502 when the areas A.sub.1 and A.sub.2 are
projected on a plane substantially parallel to the proximal end
surface 22518 of the support member 22502. Similarly, when the
implant 22500 is in the first configuration, the area A.sub.4 of
the distal retention surface 22537 is within the area A.sub.3 of
the distal end surface 22517 of the support member 22502 when the
areas A.sub.3 and A.sub.4 are projected on a plane substantially
parallel to the distal end surface 22517 of the support member
22502.
[0376] Moreover, when the implant 22500 is in the first
configuration, the biasing member 22558 exerts a force against the
locking member 22554 such that the end portion 22557 of the locking
member 22554 is disposed outside of the support member 22502 and is
received within the recess 22538 of the retention surface 22537 of
the distal retention member 22512. Accordingly, when the implant
22500 is in the first configuration, the locking member 22554
temporarily maintains the distal retention member 22512 and the
proximal retention member 22510 in the first position, as described
above.
[0377] When the implant 22500 is in the second configuration, at
least a portion of the proximal retention surface 22547 and at
least a portion of the distal retention surface 22537 are spaced
apart from the proximal end surface 22518 of the support member
22502 and the distal end surface 22517 of the support member 22502,
respectively. In this manner, when implant 22500 is in the second
configuration, the portion of the proximal retention surface 22547
and/or the portion of the distal retention surface 22537 can
contact and/or engage the spinous processes (or the associated
surrounding tissue) to limit lateral movement of the support member
22502 relative to the spinous processes.
[0378] When the proximal retention member 22510 and the distal
retention member 22512 are in the second position, a portion of the
area A.sub.2 of the proximal retention surface 22547 is outside of
the area A.sub.1 of the proximal end surface 22518 of the support
member 22502 when projected on a plane substantially parallel to
the proximal end surface 22518 of the support member 22502.
Similarly, a portion of the area A.sub.4 of the distal retention
surface 22537 is outside of the area A.sub.3 of the distal end
surface 22517 of the support member 22502 when projected on a plane
substantially parallel to the distal end surface 22517 of the
support member 22502.
[0379] Moreover, when the implant 22500 is in the second
configuration, the biasing member 22558 exerts a force against the
locking member 22554 such that the end portion 22557 of the locking
member 22554 is received, at least partially, within one of the
recesses 22539 of the outer surface 22536 of the distal retention
member 22512. Accordingly, when the implant 22500 is in the second
configuration, the locking member 22554 maintains the distal
retention member 22512 and the proximal retention member 22510 in
the second position, as described above.
[0380] Moreover, when the implant 22500 is in the second
configuration, the protrusion 22514 of the proximal retention
member 22510 can be in contact with one of the shoulder surfaces
22560 of the support member 22502. In this manner, the proximal
retention member 22510 is prevented from being rotated more than
approximately 90 degrees from the first position. Said another way,
the protrusion 22514 and the shoulder surfaces 22560 limit the
rotation of the proximal retention member 22510 relative to the
support member 22502.
[0381] The implant 22500 can be inserted into and/or removed from
the body by a deployment tool 22600, as shown in FIGS. 106-112. The
deployment tool 22600 includes a shaft 22620 and a rod 22670
movably disposed within the shaft 22620. The distal end of the
shaft 22620 includes an implant support portion 26630. The implant
support portion 26630 has a side wall 22640 having an inner surface
22641, a first end face 22644 and a second end face 22645. The
inner surface 22641, the first end face 22644 and the second end
face 22645 collectively define a receiving area 22642. As shown,
the inner surface 22641 of the side wall 22640 is configured to
complementarily receive the proximal retention member 22510 and the
distal retention member 22512 of the implant 22500. Moreover, the
first end face 22644 is set back proximally from the second end
face 22645 to accommodate the curved outer surface 22536 of the
distal retention member 22512. In this manner, as described in more
detail herein, the proximal retention member 22510 and/or the
distal retention member 22512 can be received within the receiving
area 22642 of the deployment tool 22600.
[0382] The rod 22670 includes a threaded portion 22672 that is
positioned within the receiving area 22642. The rod 22670 is
rotatable within the shaft 22620 such that the threaded portion
22672 of the rod 22670 can be threadedly engaged with the threaded
opening 22580 of the proximal retention member 22510 (see e.g.,
FIG. 107) and/or the threaded opening 22582 of the distal retention
member 22512 (see e.g., FIG. 110). In this manner, the implant
22500 can be removably secured within the receiving area 22642 of
the deployment tool 22600. The rod 22670 can be rotated within the
shaft 22620 by any suitable mechanism, such as a knob assembly (not
shown in FIGS. 106-112) of the type shown and described above with
reference to FIGS. 11-16.
[0383] In use, with the implant 22500 in the first configuration,
the proximal retention member 22510 of the implant 22500 can be
secured within the receiving area 22642 of the deployment tool
22600, as described above. As shown in FIG. 107, the proximal end
surface 22561 of the proximal retention member 22510 can be in
contact with the second end face 22645 of the deployment tool
22600.
[0384] The implant 22500 can then be inserted percutaneously until
at least a portion of the support surface 22516 of the support
member 22502 is between adjacent spinous processes (not shown in
FIGS. 106-112). In some embodiments, the implant 22500 can be
deployed via a lateral access path. The path can have any suitable
curvature and/or size, such as those described herein.
[0385] When the implant 22500 is positioned between the adjacent
spinous processes, the shaft 22620 is rotated about its center line
CL, as indicated by the arrow LL in FIG. 109. When the shaft 22620
is rotated, the position of the support member 22502 is maintained
by the adjacent spinous processes. In this manner, the proximal
retention member 22510 and the distal retention member 22512 are
rotated relative support member 22502, thereby moving the implant
22500 from the first configuration (FIG. 108) to the second
configuration (FIG. 109). The deployment tool 22600 is decoupled
from the implant 22500 by rotating the rod 22670 within the shaft
22620 until the threaded portion 22672 of the rod 22670 is no
longer engaged with the threaded opening 22580 of the proximal
retention member 22510.
[0386] The implant 22500 can be removed from and/or repositioned
within the body by positioning the deployment tool 22600 such that
the distal retention member 22512 of the implant 22500 is within
the receiving area 22642, as shown in FIGS. 110-112. As shown in
FIG. 111, when the distal retention member 22512 is within the
receiving area 22642, the distal end surface 22635 of the implant
support portion 26630 engages the portion 22557 of the locking
member 22554 and moves the locking member 22554 into the opening
22508. In this manner, the implant 22500 is "unlocked" and can be
moved from the second configuration (FIG. 111) back to the first
configuration (FIG. 112). As described above, the implant 22500 can
be moved to the first configuration by rotating the shaft 22620
about its center line CL, as indicated by the arrow MM in FIG.
112.
[0387] Although the rod 22670 is shown as being rotatable within
the shaft 22620, in other embodiments, the rod 22670 can both
rotate and translate within the shaft 22620. For example, in some
embodiments, a deployment tool can have a knob assembly similar to
the knob assembly shown and described above with reference to FIGS.
11-16.
[0388] Although the implant 22500 is shown and described without
reference to any specific dimensions, the implant 22500 can have
any suitable size to be disposed between any set of adjacent
spinous processes within a patients body (ranging, for example,
from the L4/L5 spinous processes to the C1/C2 spinous processes).
Referring to the dimensions shown in FIGS. 101 and 102, in some
embodiments, for example, the length L.sub.1 of the support member
22502 can be between 8 mm and 16 mm. In some embodiments, the
length L.sub.1 of the support member 22502 can be approximately 12
mm. Similarly, in some embodiments, the length L.sub.2 of the
proximal retention member 22510 can be between 6 mm and 12 mm. In
some embodiments, the length L.sub.2 of the proximal retention
member 22510 can be approximately 9 mm. Similarly, in some
embodiments, the length L.sub.3 of the distal retention member
22512 can be between 8 mm and 16 mm. In some embodiments, the
length L.sub.3 of the distal retention member 22512 can be
approximately 11 mm.
[0389] In some embodiments, the height H of the implant 22500 can
be between 9 mm and 22 mm. Similarly, in some embodiments, the
width W of the implant 22500 can be between 6 mm and 16 mm. In some
embodiments, for example, the height H of the implant 22500 can be
approximately 12 mm and the width W of the implant 22500 can be
approximately 8 mm. As shown in FIG. 105, the difference between
the height H and the width W is the distance D that the outermost
edge of the proximal retention member 22510 and/or the distal
retention member 22512 are spaced apart from the support surface
22516 of the support member 22502 when the implant is in the second
configuration. Said another way, the aspect ratio of the implant
22500 (H divided by W) is associated with the distance D. In some
embodiments, the aspect ratio of the implant 22500 is between
approximately 1.2 and 1.6.
[0390] FIG. 113 shows a method 23100 according to an embodiment of
the invention. The method includes disposing at least a portion of
an implant between adjacent spinous processes, 23104. The implant
includes a support member having a longitudinal axis, and a
retention member movably coupled to the support member. The implant
can be any suitable implant of the types shown and described above,
such as for example, the implant 22100.
[0391] In some embodiments, the disposing can include inserting the
implant percutaneously via a lateral access path. In some
embodiments, the disposing can include inserting the implant using
a curved tool and/or a guide member, as described herein. In some
embodiments, the method can include optionally distracting the
adjacent spinous processes before the disposing, 23102.
[0392] The retention member of the implant is then rotated from a
first position to a second position such that the retention member
retains a portion of the implant between the adjacent spinous
processes, 23106. In some embodiments, the retention member can be
rotated about an axis substantially parallel to the longitudinal
axis of the support member. In some embodiments, for example, the
support member has an end portion having a cross-sectional area
normal to the longitudinal axis of the support member. The
retention member also has a cross-sectional area normal to the
longitudinal axis of the support member. The cross-sectional area
of the retention member being within the cross-sectional area of
the distal end of the support member projected on a plane
substantially normal to the longitudinal axis and when the
retention member is in the first position. In such embodiments, the
rotating can include rotating the retention member such that a
portion of the cross-sectional area of the retention member is
outside of the cross-sectional area of the distal end of the
support member when projected on the plane substantially normal to
the longitudinal axis.
[0393] In some embodiments, the method can include optionally
locking the retention member in the second position, 23108. The
locking can include, for example, moving a locking member such that
a portion of the locking member is received within a recess defined
by the support member and/or the retention member, as described
above.
[0394] FIGS. 114-117 are schematic illustrations of an implant
24100 according to an embodiment of the invention. FIGS. 114 and
116 are posterior views of the implant 24100 in a first
configuration and a second configuration, respectively, disposed
between a first spinous process SP1 and a second spinous process
SP2 adjacent the first spinous process SP1. FIGS. 115 and 117 are
lateral views of the implant 24100 in the first configuration and
the second configuration, respectively, disposed between the first
spinous process SP1 and the second spinous process SP2. The implant
24100 includes a support member 24102 and a retention member 24112
rotatably coupled to the support member 24102.
[0395] The support member 24102 has a proximal portion 24104, a
distal portion 24106 and an outer surface 24116. The outer surface
24116 of the support member 24102 is substantially parallel to a
longitudinal axis L.sub.A of the support member 24102. Said another
way, the longitudinal axis L.sub.A and a line defined to include a
portion of the outer surface 24116 of the support member 24102 are
non-intersecting as they extend to infinity. Said yet another way,
in embodiments in which the first surface 24116 of the support
member 24102 includes at least a planar portion, every point along
the longitudinal axis L.sub.A is spaced apart from the nearest
portion of a plane defined to include the planar portion of the
first surface 24116 of the first member 22402 by a substantially
equal distance. The longitudinal axis L.sub.A can, for example,
pass lengthwise (e.g., from the proximal portion 24104 to the
distal portion 24106) through the centroid of the support member
24102 (e.g., the longitudinal axis L.sub.A can be a centroidal axis
of the support member 24102). As shown, when the implant 24100 is
disposed between the first spinous process SP1 and the second
spinous process SP2, the longitudinal axis L.sub.A can be
substantially parallel and/or coincident with a lateral axis
defined by the spinal column.
[0396] As shown, at least a portion of the outer surface 24116 of
the support member 24102 is disposed between the first spinous
process SP1 and the second spinous process SP2. In this manner, the
implant 24100 can maintain a minimal spacing between the adjacent
spinous processes SP I and SP2 during extension of the spinal
column (not shown FIGS. 114-117) while allowing flexion of the
spinal column. Moreover, in some embodiments, the implant 24100 can
distract the adjacent spinous processes SP1 and SP2.
[0397] The retention member 24112 has a first end portion 24130, a
second end portion 24132 and a central portion 24133 disposed
between the first end portion 24130 and the second end portion
24132. The retention member 24112 is rotatably coupled to the
support member 24102 such that the retention member 24112 can
rotate relative to the support member 24102 about an axis of
rotation L.sub.R substantially normal to the longitudinal axis
L.sub.A. As indicated by the arrows FF in FIGS. 116 and 117, the
retention member 24112 can rotate relative to the support member
24102 between a first position (FIGS. 114 and 115) and a second
position (FIGS. 116 and 117). When the retention member 24112 is in
the first position, the implant 24100 can be inserted such that at
least a portion of the first surface 24116 of the support member
24102 is disposed between the first spinous process SP1 and the
second spinous process SP2. When the retention member 24112 is in
the second position, the retention member 24112 limits lateral
movement of the support member 24102 along the longitudinal axis
L.sub.A and relative to the adjacent spinous processes SP1 and SP2.
The retention member 24112 can limit lateral movement of the
support member 24102, for example, by contacting the spinous
processes SP I and SP2 (e.g., either directly or through
surrounding tissue).
[0398] As shown in FIGS. 114 and 115, when the retention member
24112 is in the first position, the outermost portion of the first
end portion 24130 is spaced apart from the outer surface 24116 of
the support member 24102 by a distance Y.sub.1 along an axis
substantially normal to the longitudinal axis L.sub.A and
substantially normal to the axis of rotation L.sub.R. The distance
Y.sub.1 is such that the distance between the first end portion
24130 and the longitudinal axis L.sub.A is less than the distance
between the outer surface 24116 of the support member 24102 and the
longitudinal axis L.sub.A (i.e., the first end portion 24130 of the
retention member 24112 is "below" the outer surface 24116 of the
support member 24102 relative to the longitudinal axis L.sub.A).
Similarly, when the retention member 24112 is in the first
position, the outermost portion of the second end portion 24132 is
spaced apart from the outer surface 24116 of the support member
24102 by a distance Y.sub.2 along the axis substantially normal to
the longitudinal axis L.sub.A and substantially normal to the axis
of rotation L.sub.R. The distance Y.sub.2, which, in some
embodiments, can be equal to the distance Y.sub.1, is such that the
distance between the second end portion 24132 and the longitudinal
axis L.sub.A is less than the distance between the outer surface
24116 of the support member 24102 and the longitudinal axis L.sub.A
(i.e., the second end portion 24132 of the retention member 24112
is "below" the outer surface 24116 of the support member 24102
relative to the longitudinal axis L.sub.A). In this manner, when
the retention member 24112 is in the first position, the implant
24100 can be inserted between the spinous processes SP1 and SP2
unimpeded by first end portion 24130 of the retention member 24112
and/or the second end portion 24132 of the retention member 24112
(i.e., the retention member 24112 does not limit movement of the
support member 24102 relative to the spinous processes SP1 and
SP2).
[0399] As shown in FIGS. 116 and 117, when the retention member
24112 is in the second position, the outermost portion of the first
end portion 24130 is spaced apart from the outer surface 24116 of
the support member 24102 by a distance Y'.sub.1 along the axis
substantially normal to the longitudinal axis L.sub.A and
substantially normal to the axis of rotation L.sub.R. The distance
Y'.sub.1 is such that the distance between the first end portion
24130 and the longitudinal axis L.sub.A is greater than the
distance between the outer surface 24116 of the support member
24102 and the longitudinal axis L.sub.A (i.e., the first end
portion 24130 of the retention member 24112 is "above" the outer
surface 24116 of the support member 24102 relative to the
longitudinal axis L.sub.A). Similarly, when the retention member
24112 is in the second position, the outermost portion of the
second end portion 24132 is spaced apart from the outer surface
24116 of the support member 24102 by a distance Y'.sub.2 along the
axis substantially normal to the longitudinal axis L.sub.A and
substantially normal to the axis of rotation L.sub.R. The distance
Y'.sub.2, which in some embodiments can be equal to the distance
Y'.sub.1, is such that the distance between the second end portion
24132 and the longitudinal axis L.sub.A is greater than the
distance between the outer surface 24116 of the support member
24102 and the longitudinal axis L.sub.A (i.e., the second end
portion 24132 of the retention member 24112 is "above" the outer
surface 24116 of the support member 24102 relative to the
longitudinal axis L.sub.A). In this manner, when the retention
member 24112 is in the second position, the first end portion 24130
can contact the first spinous process SP1 and/or the second end
portion 24132 can contact the second spinous process SP2 to limit
movement of the support member 24102 relative to the spinous
processes SP I and SP2.
[0400] In use, the adjacent spinous processes SP1 and SP2 can be
distracted prior to inserting the implant 24100 into the patient.
An access passageway can be then defined to allow insertion of the
implant 24100. The passageway can have any suitable shape and can
be formed by any suitable method, as discussed herein. After the
access passageway is defined, the implant 24100 can be inserted
percutaneously and advanced along the longitudinal axis L.sub.A
until it is positioned between the spinous processes SP1 and SP2.
The implant 24100 is inserted distal portion 24106 first and with
the retention member 24112 in the first position. Once the implant
24100 is in place, the retention member 24112 is moved to the
second position to limit lateral movement of the support member
24102 with respect to the spinous processes SP1 and SP2.
[0401] If or when it is desirable to change the position of the
implant 24100 and/or remove the implant 24100, the retention member
24112 can be moved back to the first position, thereby allowing the
support member 24102 to be moved laterally. Once the support member
24102 is repositioned as desired, the retention member 24112 can be
moved back to the second position, if desired.
[0402] Although the first end portion 24130 and the second end
portion 24132 are shown and described as being "below" the outer
surface 24116 of the support member 24102 relative to the
longitudinal axis L.sub.A, in other embodiments, the first end
portion 24130 and/or the second end portion 24132 can be flush with
the outer surface 24116 of the support member 24102 (i.e., the
distance Y.sub.1 and/or the distance Y.sub.2 can be zero). In other
embodiments, the first end portion 24130 and/or the second end
portion 24132 can be above the outer surface 24116 of the support
member 24102 by a distance that does not interfere with the
insertion of the implant 24100.
[0403] Although the retention member 24112 is shown as being
coupled to the outer surface 24116 of the support member 24102, in
some embodiments, at least a portion of a retention member can be
disposed within a support member. For example, FIGS. 118-123 show
an implant 24200 according to an embodiment of the invention. FIGS.
118 and 121 are posterior views of the implant 24200 in a first
configuration and a second configuration, respectively, disposed
between a first spinous process SP1 and a second spinous process
SP2 adjacent the first spinous process SP1. FIGS. 119 and 122 are
posterior cross-sectional views of the implant 24200 in the first
configuration and the second configuration, respectively, disposed
between the spinous processes SP1 and SP2. FIGS. 120 and 123 are
cross-sectional views of the implant 24200 taken along lines A-A in
FIGS. 118 and 121, respectively.
[0404] The implant 24200 includes a support member 24202 and a
retention member 24212 movably coupled to the support member 24202.
The support member 24202 has a proximal portion 24204, a distal
portion 24206 and a side wall 24216. The side wall 24216 defines a
lumen 24208 having a longitudinal axis L.sub.A. As shown, at least
a portion of the outer surface of the side wall 24216 is in contact
with and/or adjacent to the first spinous process SP1 and/or the
second spinous process SP2 when the support member 24202 is
disposed between the first spinous process SP1 and the second
spinous process SP2. In this manner, the implant 24200 can maintain
a minimal spacing between the adjacent spinous processes SP1 and
SP2 during extension of the spinal column while allowing flexion of
the spinal column, as described herein.
[0405] The proximal portion 24204 of the support member 24202
includes a saddle surface 24253 having a curved shape that can form
a portion of a saddle 24252, as discussed in more detail herein.
The proximal portion 24204 also includes a locking member 24254
disposed within the lumen 24208 adjacent the side wall 24216. The
distal portion 24206 of the support member 24202 has a curved shape
to facilitate insertion of the implant 24200 into the body.
[0406] The retention member 24212 has a first end portion 24230, a
second end portion 24232 and a central portion 24233 disposed
between the first end portion 24230 and the second end portion
24232. The central portion 24233 of the retention member 24212 is
disposed within the lumen 24208 of the support member 24202. The
second end portion 24232 includes a saddle surface 24251 having a
curved shape that can form a portion of a saddle 24252, as
discussed in more detail herein.
[0407] The retention member 24212 is rotatably coupled to the
support member 24202 such that the retention member 24212 can
rotate relative to the support member 24202 about an axis of
rotation L.sub.R substantially normal to the longitudinal axis
L.sub.A. As indicated by the arrows GG in FIGS. 122 and 123, the
retention member 24212 can rotate relative to the support member
24202 between a first position (FIGS. 118-120) and a second
position (FIGS. 121-123). When the retention member 24212 is in the
first position, the implant 24200 can be inserted such that at
least a portion of the side wall 24216 of the support member 24202
is disposed between the first spinous process SP1 and the second
spinous process SP2. When the retention member 24212 is in the
second position, the retention member 24212 limits movement of the
support member 24202 along the longitudinal axis L.sub.A and
relative to the adjacent spinous processes SP1 and SP2. The second
end portion 24232 of the retention member 24212 can limit movement
of the support member 24202, for example, by contacting and/or
engaging the spinous processes SP1.
[0408] As shown in FIGS. 119 and 120, when the retention member
24212 is in the first position, the second end portion 24232 of the
retention member 24212 is disposed within the lumen 24208 of the
support member 24202. When the retention member 24212 is in the
first position, the implant 24200 can be inserted such that a
portion of the support member 22202 is disposed between the first
spinous process SP1 and the second spinous process SP2.
[0409] As shown in FIGS. 121-123, when the retention member 24212
is in the second position, the second end portion 24232 is disposed
through an opening 24209 in the side wall 24208 and outside of the
distal end portion 24206 of the support member 24202. When the
retention member 24212 is in the second position, the outer surface
of the side wall 22216 of the support member 24202 and the saddle
surface 22251 of the second end portion 24232 of the retention
member 24212 collectively form a portion of a saddle 24252
configured to receive a portion of the spinous process SP1. The
saddle 24252 can receive and/or engage a portion of the spinous
process SP1 and/or its surrounding tissue to limit movement of the
support member 24202 along the longitudinal axis L.sub.A and
relative to the spinous processes SP1 and SP2. In some embodiments,
the saddle 24252 and/or the saddle surface 24251 can have a curved
surface that substantially corresponds to a shape and/or a size of
the spinous process SP1. In some embodiments, the shape and/or size
of the saddle surface 24251 can be configured to more evenly
distribute forces between the saddle 24252 and the spinous process
SP1. In some embodiments, the saddle surface 24251 and the outer
surface of the side wall 24216 of the can form a substantially
continuous surface.
[0410] Moreover, when the retention member 24212 is in the second
position, the first end portion 24230 of the retention member 24212
engages with the locking member 24254 to maintain the retention
member 24212 in the second position. In some embodiments, the
locking member 24254 can be configured to temporarily maintain the
retention member 24212 in the second position. In other
embodiments, the locking member 24254 can be configured to fixedly
maintain the retention member 24212 in the second position. In some
embodiments, the locking member 24254 can be, for example, a
protrusion defining a recess configured to receive and/or
releasably retain the first end portion 24230 of the retention
member 24212. In other embodiments, the locking member 24254 can be
monolithically formed as part of the side wall 24216. In such
embodiments, for example, the locking member 24254 can be a recess
configured to matingly receive (e.g., via an interference fit) the
first end portion 24230 of the retention member 24212 to maintain
the retention member 24212 in the second position.
[0411] Said another way, when the retention member 24212 is in the
first position, a cross-sectional area A.sub.2 of the second end
portion 24232 of the retention member 24212 is within a
cross-sectional area A.sub.1 of the support member 24202 when
projected on a plane substantially normal to the longitudinal axis
L.sub.A (see FIG. 120). When the retention member 24212 is in the
second position, at least a portion of the cross-sectional area
A.sub.2 of the retention member 24212 is outside of the
cross-sectional area A.sub.1 of the support member 24202 when
projected on a plane substantially normal to the longitudinal axis
L.sub.A (see FIG. 123). Although the cross sectional area A.sub.2
of the retention member 24212 and the cross-sectional area A.sub.1
of the support member 24202 are shown as being within a plane
normal to the longitudinal axis L.sub.A when viewed from a lateral
view (e.g., FIGS. 120 and 123), the cross sectional areas A.sub.2
and A.sub.1 can be within a plane normal to the longitudinal axis
L.sub.A when viewed from a posterior view (e.g., FIGS. 119 and
122).
[0412] In some embodiments, the implant 24200 can include a biasing
member, such as, for example, a torsional spring, disposed between
the retention member 24212 and the support member 24202. In this
manner, the retention member 24212 can be biased in the second
position (i.e., such that the second end portion 24232 of the
retention member 24212 is maintained in engagement with the first
spinous process SP1 and/or its surrounding tissue). In other
embodiments, the retention member 24212 can be biased in the first
position (i.e., such that the second end portion 24232 of the
retention member 24212 is maintained within the lumen 24208 of the
support member 24202).
[0413] Although the first end portion 24230 of the retention member
24212 and the second end portion 24232 of the retention member
24212 are shown as being within the lumen 24208 of the support
member 24202 when the retention member 24212 is in the first
position, in other embodiments, at least a portion of the first end
portion 24230 and/or the second end portion 24232 can be disposed
outside of the support member 24202 when the retention member 24212
is in the first position. For example, in some embodiments, a
second end portion of a retention member can extend outside of a
distal end portion of a support member along a longitudinal axis of
the support member when the retention member is in a first
position. In such embodiments, for example, a cross-sectional area
of the second end portion of the retention member can be within a
cross-sectional area of the support member when projected on a
plane substantially normal to the longitudinal axis and when the
retention member is in the first position, as described above.
[0414] Although the implant 24200 is shown and described as
including a retention member 24212, in other embodiments, an
implant can include multiple retention members. For example, FIGS.
124-127 show an implant 24300 according to an embodiment of the
invention in a first configuration (FIGS. 124 and 125) and a second
configuration (FIGS. 126 and 127). The implant 24300 includes a
support member 24302, a first retention member 24312 and a second
retention member 24310. The first retention member 24312 and the
second retention member 24310 are rotatably coupled to the support
member by a pin 24309.
[0415] As described above, the support member 24302 has a proximal
portion 24304, a distal portion 24306 and a side wall 24316. The
side wall 24316 defines a lumen 24308 having a longitudinal axis
L.sub.A. As shown, at least a portion of the outer surface of the
side wall 24316 is in contact the first spinous process SP1 and/or
the second spinous process SP2 when the support member 24302 is
disposed between the first spinous process SP1 and the second
spinous process SP2.
[0416] The first retention member 24312 has a proximal end portion
24330, a distal end portion 24332 and a central portion 24333
disposed between the proximal end portion 24330 and the distal end
portion 24332. The central portion 24333 of the first retention
member 24312 is disposed within the lumen 24308 of the support
member 24302. The proximal end portion 24330 of the first retention
member 24312 and the distal end portion 24332 of the first
retention member 24312 are disposed outside of the lumen 24308. The
distal end portion 24332 of the first retention member 24312 has a
curved shape (e.g., a tapered end portion) to facilitate insertion
of the implant 24300 into the body. The distal end portion 24332 of
the first retention member 24312 also includes a tip 24335 to
facilitate insertion of the implant 24300 into the body. In some
embodiments, for example, the distal end portion 24332 of the first
retention member 24312 can displace a bodily tissue when the
implant 24300 is inserted into the body. In some embodiments, the
distal end portion 24332 of the first retention member 24312 can
dilate a bodily tissue, such as the supraspinous ligament, when the
implant 24300 is inserted into the body. In some embodiments, the
distal end portion 24332 of the first retention member 24312 can
distract a space between adjacent spinous processes when the
implant 24300 is inserted into the body.
[0417] Similarly, the second retention member 24310 (not shown in
FIG. 111) has a proximal end portion 24340, a distal end portion
24342 and a central portion 24343 disposed between the proximal end
portion 24340 and the distal end portion 24342. The central portion
24343 second retention member 24310 is disposed within the lumen
24308 of the support member 24302. The proximal end portion 24340
of the second retention member 24310 and the distal end portion
24342 of the second retention member 24310 are disposed outside of
the lumen 24308. The distal end portion 24342 of the second
retention member 24310 has a curved shape (e.g., a tapered end
portion) to facilitate insertion of the implant 24300 into the
body.
[0418] The distal end portion 24342 of the second retention member
24310 also includes a tip 24345 to facilitate insertion of the
implant 24300 into the body. In some embodiments, for example, the
distal end portion 24342 of the second retention member 24310 can
displace a bodily tissue when the implant 24300 is inserted into
the body. In some embodiments, the distal end portion 24342 of the
second retention member 24310 can dilate a bodily tissue, such as
the supraspinous ligament, when the implant 24300 is inserted into
the body. In some embodiments, the distal end portion 24342 of the
second retention member 24310 can distract a space between adjacent
spinous processes when the implant 24300 is inserted into the
body.
[0419] In some embodiments, the shape of the distal end portion
24342 of the second retention member 24310 can be similar (e.g., a
mirror image) to the shape of the distal end portion 24332 of the
first retention member 24312. Said another way, in some
embodiments, the distal end portion 24342 of the second retention
member 24310 and the distal end portion 24332 of the first
retention member 24312 can cooperatively form a substantially
continuous surface.
[0420] The first retention member 24312 and the second retention
member 24310 are rotatably coupled to the support member 24302
about an axis of rotation L.sub.R substantially normal to the
longitudinal axis L.sub.A. As indicated by the arrows HH in FIGS.
126 and 127, the first retention member 24312 and/or the second
retention member 24310 can rotate relative to the support member
24202 to place the implant 24300 in a first configuration (FIGS.
124 and 125) and a second configuration (FIGS. 126 and 127). When
in the first configuration, the implant 24300 can be inserted such
that at least a portion of the side wall 24316 of the support
member 24302 is disposed between the first spinous process SP1 and
the second spinous process SP2. When in the second configuration,
first retention member 24312 and/or the second retention member
24310 limit lateral movement of the support member 24302 along the
longitudinal axis L.sub.A and relative to the adjacent spinous
processes SP1 and SP2.
[0421] As shown in FIGS. 124 and 125, when the implant 24300 is in
the first configuration, the outer surface of the proximal end
portion 24330 of the first retention member 24312 is flush with the
outer surface 24316 of the support member 24302 (i.e., the outer
surface of the proximal end portion 24330 is spaced apart from the
outer surface 24316 of support member 24302 by a nominal gap along
a direction normal to the longitudinal axis L.sub.A). Additionally,
the outer surface of the distal end portion 24332 of the first
retention member 24312 is flush with the outer surface 24316 of the
support member 24302 (i.e., the outer surface of the distal end
portion 24332 is spaced apart from the outer surface 24316 of
support member 24302 by a nominal gap along a direction normal to
the longitudinal axis L.sub.A). Said another way, when the implant
24300 is in the first configuration, the proximal end portion 24330
of the first retention member 24312, the distal end portion 24332
of the first retention member 24312 and the outer surface 24316 of
the support member 24302 collectively form a substantially
continuous surface.
[0422] Similarly, when the implant 24300 is in the first
configuration, the outer surface of the proximal end portion 24340
of the second retention member 24310 is flush with the outer
surface 24316 of the support member 24302 (i.e., the outer surface
of the proximal end portion 24340 is spaced apart from the outer
surface 24316 of support member 24302 by a nominal gap along an
offset axis L.sub.O normal to the longitudinal axis L.sub.A and
substantially normal to the axis of rotation L.sub.R).
Additionally, the outer surface of the distal end portion 24342 of
the second retention member 24310 is flush with the outer surface
24316 of the support member 24302 (i.e., the outer surface of the
distal end portion 24342 is spaced apart from the outer surface
24316 of support member 24302 by a nominal gap along the offset
axis L.sub.O). Said another way, when the implant 24300 is in the
first configuration, the proximal end portion 24340 of the second
retention member 24310, the distal end portion 24342 of the second
retention member 24310 and the outer surface 24316 of the support
member 24302 collectively form a substantially continuous
surface.
[0423] As shown in FIGS. 126 and 127, when the implant 24300 is in
the second configuration, the outermost edge of the proximal end
portion 24330 of the first retention member 24312 is spaced apart
from the outer surface 24316 of the support member 24302 by a
distance Y.sub.5 along the offset axis L.sub.O. The distance
Y.sub.5 is such that the distance between the outermost edge of the
proximal end portion 24330 and the longitudinal axis L.sub.A is
greater than the distance between the outer surface 24316 of the
support member 24302 and the longitudinal axis L.sub.A (i.e., the
proximal end portion 24330 of the first retention member 24312 is
"outside" the outer surface 24316 of the support member 24302
relative to the longitudinal axis L.sub.A).
[0424] Similarly, when the implant 24300 is in the second
configuration, the outermost edge of the distal end portion 24332
of the first retention member 24312 is spaced apart from the outer
surface 24316 of the support member 24302 by a distance Y.sub.6
along the offset axis L.sub.O. The distance Y.sub.6 is such that
the distance between the outermost edge of the distal end portion
24332 and the longitudinal axis L.sub.A is greater than the
distance between the outer surface 24316 of the support member
24302 and the longitudinal axis L.sub.A (i.e., the distal end
portion 24332 of the first retention member 24312 is "outside" the
outer surface 24316 of the support member 24302 relative to the
longitudinal axis L.sub.A). In this manner, when the implant 24300
is in the second configuration, the proximal end portion 24330 of
the first retention member 24312 and/or the distal end portion
24332 of the first retention member 24312 can contact the first
spinous process SP1, the second spinous process SP2 and/or the
surrounding tissue to limit lateral movement of the support member
24302 relative to the spinous processes SP1 and SP2.
[0425] Similarly, when the implant 24300 is in the second
configuration, the outermost edge of the proximal end portion 24340
of the second retention member 24310 is spaced apart from the outer
surface 24316 of the support member 24302 by a distance Y.sub.7
along the offset axis L.sub.O. Said another way, the proximal end
portion 24340 of the second retention member 24312 is "outside" the
outer surface 24316 of the support member 24302 relative to the
longitudinal axis L.sub.A. The outermost edge of the distal end
portion 24342 of the second retention member 24310 is spaced apart
from the outer surface 24316 of the support member 24302 by a
distance Y.sub.8 along the offset axis L.sub.O. Said another way,
the distal end portion 24342 of the second retention member 24310
is "outside" the outer surface 24316 of the support member 24302
relative to the longitudinal axis L.sub.A. In this manner, when the
implant 24300 is in the second configuration, the proximal end
portion 24340 of the second retention member 24310 and/or the
distal end portion 24342 of the second retention member 24310 can
contact the first spinous process SP1, the second spinous process
SP2 and/or the surrounding tissue to limit lateral movement of the
support member 24302 relative to the spinous processes SP1 and
SP2.
[0426] In some embodiments, the first retention member 24312 and
the second retention member 24310 can be moved relative to the
support member 24302 serially. In other embodiments, the first
retention member 24312 and the second retention member 24310 can be
moved relative to the support member 24302 simultaneously. In yet
other embodiments, only one of the first retention member 24312 or
the second retention member 24310 can be moved relative to the
support member 24302.
[0427] FIGS. 128 and 129 show an implant 24400 according to an
embodiment of the invention in a first configuration (FIG. 128) and
a second configuration (FIG. 129). The implant 24400 includes a
first elongate member 24412 and a second elongate member 24410. As
shown, the implant 24400 is configured to be disposed between a
first spinous process SP1 and a second spinous process SP2 to
maintain a minimal spacing between the spinous processes during
extension of the spinal column. The first elongate member 24412 and
the second elongate member 24410 are rotatably coupled together by
a pin 24409.
[0428] The first elongate member 24412 has a proximal end portion
24430 and a distal end portion 24432 and defines a longitudinal
axis L.sub.A1. The distal end portion 24432 of the first elongate
member 24412 has a curved shape (e.g., a tapered end portion) to
facilitate insertion of the implant 24400 into a body. The distal
end portion 24432 of the first retention member 24412 also includes
a tip 24435 to facilitate insertion of the implant 24400 into the
body. In some embodiments, for example, the distal end portion
24432 of the first retention member 24412 can displace a bodily
tissue when the implant 24400 is inserted into the body. In some
embodiments, the distal end portion 24432 of the first retention
member 24412 can dilate a bodily tissue, such as the supraspinous
ligament, when the implant 24400 is inserted into the body. In some
embodiments, the distal end portion 24432 of the first retention
member 24412 can distract a space between adjacent spinous
processes when the implant 24400 is inserted into the body.
[0429] The first elongate member 24412 also has a first surface
24436 and a second surface 24437 opposite the first surface 24436.
As described in more detail herein, the first surface 24436 and the
second surface 24437 are configured to contact and/or engage the
first spinous process SP1 and/or the second spinous process SP2,
respectively to limit movement of the implant 24400 along the
longitudinal axis L.sub.A1 and relative to the adjacent spinous
processes SP1 and SP2. Although the first surface 24436 and the
second surface 24437 are shown and described as being substantially
parallel to each other and substantially parallel to the
longitudinal axis L.sub.A1, in other embodiments, the first surface
24436 and/or the second surface 24437 can be angularly offset from
each other and/or angularly offset from the longitudinal axis
L.sub.A1. Similarly, although the first surface 24436 and the
second surface 24437 are shown as being linear when viewed from the
posterior view, in some embodiments, the first surface 24436 and/or
the second surface 24437 can have a non-linear shape.
[0430] Similarly, as shown in FIG. 129, the second elongate member
24410 also has a proximal end portion 24440 and a distal end
portion 24442 and defines a longitudinal axis L.sub.A2. The distal
end portion 24442 of the second elongate member 24410 has a curved
shape (e.g., a tapered end portion) to facilitate insertion of the
implant 24400 into the body. The distal end portion 24442 of the
second retention member 24410 also includes a tip 24445 to
facilitate insertion of the implant 24400 into the body. In some
embodiments, for example, the distal end portion 24442 of the
second retention member 24410 can displace a bodily tissue when the
implant 24400 is inserted into the body. In some embodiments, the
distal end portion 24442 of the second retention member 24410 can
dilate a bodily tissue, such as the supraspinous ligament, when the
implant 24400 is inserted into the body. In some embodiments, the
distal end portion 24442 of the second retention member 24410 can
distract a space between adjacent spinous processes when the
implant 24400 is inserted into the body.
[0431] The second elongate member 24410 also has a first surface
24446 and a second surface 24447 opposite the first surface 24446.
As described in more detail herein, the first surface 24446 and the
second surface 24447 are configured to contact and/or engage the
first spinous process SP1 and the second spinous process SP2,
respectively, either directly or indirectly, to limit movement of
the implant 24400 along the longitudinal axis L.sub.A1 and relative
to the adjacent spinous processes SP1 and SP2. Although the first
surface 24446 and the second surface 24447 are shown and described
as being substantially parallel to each other and substantially
parallel to the longitudinal axis L.sub.A2, in other embodiments,
the first surface 24446 and/or the second surface 24447 can be
angularly offset from each other and/or angularly offset from the
longitudinal axis L.sub.A2. Similarly, although the first surface
24446 and the second surface 24447 are shown as being linear when
viewed from the posterior view, in some embodiments, the first
surface 24446 and/or the second surface 24447 can have a non-linear
shape.
[0432] As indicated by the arrow II in FIG. 129, the first elongate
member 24412 and the second elongate member 24410 can rotate
relative to each other about an axis of rotation substantially
normal to the longitudinal axis L.sub.A to move the implant 24400
between a first configuration (FIG. 128) and a second configuration
(FIG. 129). When the implant 24400 is in the first configuration,
the longitudinal axis L.sub.A1 of the first elongate member 24412
is substantially parallel to the longitudinal axis L.sub.A2 of the
second elongate member 24410. Similarly stated, when the implant
24400 is in the first configuration, the first surface 24436 of the
first elongate member 24412 is aligned with the first surface 24446
of the second elongate member 24410 (i.e., the first surface 24436
and the first surface 24446 form a substantially continuous
surface) and the second surface 24437 of the first elongate member
24412 is aligned with the second surface 24447 of the second
elongate member 24410 (i.e., the second surface 24437 and the
second surface 24447 form a substantially continuous surface).
Accordingly, when in the first configuration, the implant 24400 can
be disposed between the first spinous process SP1 and the second
spinous process SP2.
[0433] As shown in FIG. 129, when the implant 24400 is in the
second configuration, the longitudinal axis L.sub.A1 of the first
elongate member 24412 intersects the longitudinal axis L.sub.A2 of
the second elongate member 24410 at an angle .THETA.. Moreover,
when the implant 24400 is in the second configuration, the first
surface 24436 of the first elongate member 24412 and the first
surface 24446 of the second elongate member 24410 collectively form
a portion of a first saddle 24452 configured to receive a portion
of the spinous process SP1. Similarly, the second surface 24437 of
the first elongate member 24412 and the second surface 24447 of the
second elongate member 24410 collectively form a portion of a
second saddle 24453 configured to receive a portion of the spinous
process SP2. The first saddle 24452 and the second saddle 24453 can
be of any suitable shape and size, as discussed above. In this
manner, when the implant 24400 is in the second configuration, the
first saddle 24452 and/or the second saddle 24453 limit movement of
the implant relative to the adjacent spinous processes SP1 and
SP2.
[0434] FIG. 130 shows a method 25100 according to an embodiment of
the invention. The method includes disposing at least a portion of
an implant between a first spinous process and a second spinous
process, 23104. The implant includes a support member and a
retention member rotatably coupled to the support member. The
implant can be any suitable implant of the types shown and
described above, such as for example, the implant 24100.
[0435] In some embodiments, the disposing can include inserting the
implant percutaneously via a lateral access path. In some
embodiments, the disposing can include inserting the implant using
a curved tool and/or a guide member, as described herein. In some
embodiments, the method can include optionally distracting the
adjacent spinous processes before the disposing, 25102.
[0436] The retention member of the implant is rotated relative to
the support member from a first position to a second position such
that a first end portion of the retention member is disposed
outside of a proximal end portion of the support member and a
second end portion of the retention member is disposed outside a
distal end portion of the support member, 25106. In this manner,
the first end portion of the retention member and the second end
portion of the retention member can cooperatively limit movement of
the support member along the longitudinal axis and relative to the
first spinous process and the second spinous process. In some
embodiments, the retention member can be rotated about an axis
substantially normal to a longitudinal axis of the support
member.
[0437] In some embodiments, the method can include optionally
locking the retention member in the second position, 25108. The
locking can include, for example, moving a portion of the retention
member into engagement with a locking member, as described
above.
[0438] FIG. 131 shows a method 25200 according to an embodiment of
the invention. The method includes disposing at least a portion of
an implant between a first spinous process and a second spinous
process, 25204. The implant includes a first elongate member and a
second elongate member rotatably coupled to the first elongate
member. The implant can be any suitable implant of the types shown
and described above, such as for example, the implant 24400.
[0439] In some embodiments, the disposing can include inserting the
implant percutaneously via a lateral access path. In some
embodiments, the disposing can include inserting the implant using
a curved tool and/or a guide member, as described herein. In some
embodiments, the method can include optionally distracting the
adjacent spinous processes before the disposing, 25202.
[0440] The second elongate member is rotated relative to the first
elongate member about an axis substantially normal to a
longitudinal axis of the first elongate member from a first
position to a second position such that a portion of the first
elongate member and a portion of the second elongate member engage
the first spinous process, 25206. In this manner, the first
elongate member and the second elongate member cooperatively limit
movement of the first elongate member along the longitudinal axis
and relative to the first spinous process and the second spinous
process.
[0441] In some embodiments, the method can include optionally
maintaining the position of the second elongate member relative to
the first elongate member after the rotating, 25208. The
maintaining can include, for example, moving a portion of the first
elongate member and/or a portion of the second elongate member into
engagement with a locking member, as described above.
[0442] FIG. 132 is a schematic illustration of an example of a
medical device that can be used to perform the methods described
herein. A medical device can include an implant, a guide member
and/or an insertion tool, as described herein. The various
components of the medical device can be provided in some
embodiments, for example, as a kit. Such a kit can include one or
more implants, one or more guide members, and/or one or more
insertion tools as described herein. A medical device 26100
includes an implant 26120 and a guide member 26130 that can be
releasably coupled to the implant 26120. The guide member 26130 can
be percutaneously inserted into a body and the implant 26120 can be
inserted into the body and moved within the body using an insertion
tool 26140 that can be releasably coupled to the implant 26120. The
insertion tool 26140 can be, for example, coupled to a proximal end
portion of the implant 26120. The insertion tool 26140 can apply a
longitudinal force to a proximal end of the implant 26120 to move
the implant 26120 through a portion of a body. In some embodiments,
the medical device 26100 can be inserted through a cannula (not
shown). The guide member 26130 can be releasably coupled to a
distal end portion of the implant 26120 and can be used to guide
the implant 26120 as the implant 26120 is moved by the insertion
tool 26140. For example, the guide member 26130 can lead the
implant 26120 along a path defined by a shape of the guide member
26130 as described in more detail below.
[0443] The guide member 26130 can include a distal end having a
sharp tip (not shown in FIG. 132) that can be percutaneously
inserted into a body through an exterior location on the body. The
guide member 26130 can have a curved shape to allow the guide
member 26130 to define a curved path as the guide member 26130 is
maneuvered through a body. A proximal end portion of the guide
member 26130 can have a connector or connector portion configured
to releasably couple the guide member 26130 to the implant 26120. A
separate connector member can be coupled to the guide member 26130,
or the guide member 26130 can have a connector portion formed
monolithically with the guide member 26130. For example, the guide
member 26130 can include a threaded portion configured to
threadedly couple to a threaded portion of a distal end portion of
the implant 26120. In other embodiments, a proximal end portion of
the guide member 26130 can include a key member (not shown) that
can be received in, and releasably locked, within a keyway or
opening at a distal end portion of the implant 26120. In some
embodiments, a proximal end portion of the guide member 26130 is
received within an opening in the distal end portion of the implant
26120 and held in place within the opening, in part, by a
longitudinal force exerted on the implant 26120 by an insertion
tool 26140.
[0444] The guide member 26130 can be formed, for example, as a
flexible wire or a flexible needle having a lumen there through.
The guide member can be formed such that it is sufficiently
flexible about an axis normal to a longitudinal axis of the guide
member 26130 and is sufficiently rigid when a force along the
longitudinal axis such that the guide member 26130 substantially
maintains its shape when percutaneously inserted into a body.
[0445] The insertion tool 26140 includes a distal end portion
configured to be releasably coupled to the implant 26120. For
example, the distal end portion of the insertion tool 26140 can
define an opening and an interior space that can receive the
proximal end portion of the implant 26120 therein. The proximal end
portion of the implant 26120 can be sized to fit within the
interior space of the distal end portion of the insertion tool
26140. When the insertion tool 26140 moves within a body in a
direction toward the implant 26120, the implant 26120 will move in
the same direction, but when the insertion tool 26140 is moved in
an opposite direction, away from the implant 26120, the insertion
tool 26140 will be removed from the proximal end portion of the
implant 26120.
[0446] The insertion tool 26140 can have various different, shapes,
sizes and configurations and include different coupling means to
releasably couple the insertion tool 26140 to the implant 26120.
Likewise, the proximal end portion of the implant 26120 can include
various coupling means for coupling the implant 26120 to an
insertion tool 26140. For example, in some embodiments, the
insertion tool can be releasably coupled to the implant via a
quick-connect coupling as shown and described in U.S. patent
application Ser. No. 11/693,496, incorporated herein by reference.
In some embodiments, the insertion tool is releasably coupled to
the implant via a locking member disposed on the insertion tool
also as shown and described in the above-mentioned application. In
some embodiments, the insertion tool is releasably coupled to the
implant using a key and keyway as shown and described herein with
reference to FIGS. 15 and 16. For example, the distal end portion
of the implant can include multiple notches that can matingly
receive corresponding protrusions on the distal end portion of the
insertion tool.
[0447] In use, a distal end of the guide member 26130 is
percutaneously inserted into a body through a first location on the
body. The implant 26120 can be coupled to the guide member 26130
before or after at least the distal end of the guide member 26130
has been inserted into the body. For example, the guide member
26130 can be inserted partially into the body and then the implant
26120 inserted into the body thereafter.
[0448] In some embodiments, the guide member 26130 has a length
such that the guide member 26130 can be inserted into the body at a
first location, and moved or pushed through the body along a curved
path until the distal end of the guide member 26130 exits the body
at a second location. In such an embodiment, the implant 26120 is
inserted into the body after the distal end of the guide member
26130 exits the body at the second location.
[0449] In some embodiments, the distal end of the guide member
26130 is inserted through a first opening in a body at a first
distance from a centerline of the body. The guide member 26130 can
then be advanced, either with or without the implant 26120 being
advanced within the body, until the distal end of the guide member
26130 exits the body at a second opening at a second distance from
the centerline of the body and on a second side of the centerline
of the body. In some embodiments, the first distance is
substantially equal to the second distance. In other embodiments,
the first distance is not equal to the second distance.
[0450] With the distal end portion of the implant 26120 coupled to
the proximal end portion of the guide member 26130, the insertion
tool 26140 can be used to push or advance the implant 26120 through
the body to a selected position within the body. In some
embodiments, an imaging device is used to assist in the positioning
of the implant 26120 at a desired location within the body. As the
implant 26120 is advanced in the body, the implant 26120 will move
or advance the guide member 26130 through the body along a path
defined by the guide member 26130. The implant 26120 can be moved,
for example, to a position between two adjacent bone structures,
such as, between two adjacent spinous processes. In doing so, the
distal end of the guide member 26130 will exit the body at a second
location, if not already exited prior to inserting or moving the
implant 26120. After the implant 26120 is positioned in the desired
location within the body (e.g., between bone structures), the guide
member 26130 can be released from the implant 26120. For example,
the distal end of the guide member 26130 positioned outside of the
body at the second location can be grasped, and the releasable
coupling between the guide member 26130 and the implant 26120 can
be decoupled to release the guide member 26130 from the implant
26120.
[0451] The insertion tool 26140 can also be released from the
implant 26120 and removed from the body before, after or
simultaneously with the removal of the guide member 26130. After
removing both the guide member 26130 and the insertion tool 26149,
the implant 26120 will be left within the body at the desired
implantation site.
[0452] FIG. 133 is an exploded view of an embodiment of a medical
device including an implant, a guide member and insertion tool. The
various components of the medical device can be provided, for
example, as a kit. The kit can include one or more implants, and/or
one or more guide members, and/or one or more insertion tools. A
medical device 26200 includes an implant 26220 having a proximal
end portion 26222 and distal end portion 26224. The distal end
portion 26224 of the implant 26220 defines an opening 26228. The
implant 26220 also includes a threaded portion 26226 disposed at
the distal end portion 26224 as illustrated in FIGS. 133 and
134.
[0453] A guide member 26230 has a proximal end portion 26236, a
distal end portion 26234 and a distal end 26238 having a sharpened
or tapered shape. The proximal end portion 26232 of the guide
member 26230 includes a threaded portion 26236. The threaded
portion 26236 is configured to matingly couple to the corresponding
threaded portion 26226 of the implant 26220. The distal end 26238
can be percutaneously inserted through an exterior location of a
body and passed through the body until the distal end 26238 exits
the body at a second exterior location of the body.
[0454] An insertion tool 26240 includes a middle portion 26242, a
proximal end portion (not shown) and a distal end portion 26244. In
some embodiments, the proximal end portion, the distal end portion
26244, and the middle portion 26242 are monolithically formed. In
some embodiments, some or all of the proximal end portion, the
distal end portion 26244, and the middle portion 26242 are formed
as separate components and coupled together. The distal end portion
26244 defines an opening 26248 that is in communication with an
interior space 26250 as best shown in FIG. 135. The proximal end
portion 26222 of the implant 26220 can be received through the
opening 26248 and disposed within the interior space 26250 to
releasably couple the implant 26220 to the insertion tool
26240.
[0455] The guide member 26230 and the insertion tool 26240 can be
used to deliver the implant 26220 to an implantation site within a
body. FIGS. 136 and 137 illustrate an example of a procedure to
deliver the implant 26220 to a location between adjacent spinous
processes. As shown in FIG. 136, the guide member 26230 is
percutaneously inserted through a first exterior location B1 in a
body B. As described above, the implant 26220 can be coupled to the
guide member 26230 before or after the guide member 26230 is
inserted into a body. To couple the guide member 26230 to the
implant 26220, the threaded portion 26236 of the guide member 26230
is rotated with respect to the mating threaded portion 26226 of the
implant 26220. The curved shape of the guide member 26230 defines a
curved path through the body as the guide member 26230 is moved
through the body, indicated by the dashed-line path in FIG. 136. In
this example procedure, the path of the guide member 26230 passes
between adjacent spinous processes (only the inferior spinous
process S1 is shown in FIG. 136). In this embodiment, the length of
the guide member 26230 is such that the implant 26220 is still
disposed outside the body B when the guide member 26230 is passed
between the spinous processes.
[0456] The insertion tool 26240 is coupled to the proximal end
portion of the implant 2620 to push or move the implant 26220
through the body B, as shown in FIG. 137. FIG. 137 is a top view
illustrating a view above a second spinous process S2 superior to
the spinous process S1. As the insertion tool 26240 moves or
advances the implant 26220 to a position between the inferior
spinous process S1 and the superior spinous process S2, the guide
member 26230 will be advanced along the curved path defined by the
curve of the guide member 26230. The guide member 26230 will be
advanced until the distal tip 26238 exits a second exterior
location B2 on the body B.
[0457] Once the implant 26220 is positioned in the desired location
within the body, the insertion tool 26240 can be decoupled from the
implant 26220 by pulling the insertion tool 26240 proximally and
out of the body B. The guide member 26230 can also be removed from
the implant 26220 by turning the guide member counter-clockwise to
decouple the threaded coupling between the implant 26220 and the
guide member 26230. It may be desirable to remove the guide member
26230 before removing the insertion tool 26240 so that the
insertion tool 26240 can be held to stabilize the implant 26220
while decoupling the guide member 26230 from the implant 26220.
After removing both the guide member 26230 and the insertion tool
26240, the implant 26220 will remain implanted between the two
spinous processes S1 and S2.
[0458] FIG. 138 illustrates an embodiment of a guide member that
has sufficient length to extend within a body between an ingress
location and an egress location before inserting an implant into
the body. A guide member 26330 is shown percutaneously inserted
through a first location B1 on a body B, passing between adjacent
spinous processes (only an inferior spinous process S1 is shown),
and a distal end 26338 of the guide member 26330 exiting the body B
at an exit location B2. The ingress location B1 is at a distance Y
from a centerline C of the body B, and the egress location B2 is at
a distance X from the centerline C of the body B on an opposite
side of the centerline C. In this embodiment, the distance X and
the distance Y is substantially equal. In other embodiments, the
distance X and the distance Y are not equal.
[0459] As stated previously, a distal end portion of an implant
(not shown) can be releasably coupled to a proximal end portion
26332 of the guide member 26330, either before or after the guide
member 26330 has been inserted into the body B. Although not needed
for all embodiments, an optional insertion tool (not shown) can be
used to advance the implant and guide member 26330 along a curved
path defined by the guide member 26330 as described previously.
Alternatively, after the distal end 26338 is positioned outside of
the egress location B2, the distal end 26338 of the guide member
26330 can be grasped (e.g., by hand, with forceps, or using another
instrument) and pulled such that the implant is moved (e.g.,
pulled) through the body B and to a desired implantation site. For
example, the implant can be pulled through the body B along the
curved path defined by the guide member 26330 and is positioned
between adjacent spinous processes.
[0460] FIGS. 139-141 illustrate another embodiment of a medical
device. A medical device 26400 includes an implant 26420 and guide
member 26430. The implant 26420 and guide member 26430 are similar
to the embodiments illustrated in FIG. 133 except in this
embodiment the coupling between the implant 26420 and the guide
member 26430 includes a key configured to be received within a
keyway. The implant 26420 has a proximal end portion 26426 and a
distal end portion 26424. The distal end portion 26424 defines an
opening 26428 and a slot or keyway 26458, as shown in the distal
end view of the implant 26420 of FIG. 140. The slot 26458 is in
fluid communication with an interior space 26460 within the implant
26420. The guide member 26430 has a distal end portion 26434 that
includes a sharp distal end or tip 26438. The guide member 26430
also has a proximal end portion 26432 that includes a key 26456.
The key 26456 can be received through the opening 26428 and the
slot 26458 to releasably couple the guide member 26430 to the
implant 26420.
[0461] For example, to couple the guide member 26430 to the implant
26420, the guide member 26430 is initially turned or oriented such
that the key 26456 is substantially aligned with the opening 26428
and slot 26458. The key 26456 is then placed through the slot 26458
and then turned (e.g., 90 degrees) such that the key 26456 is at
least partially misaligned with the slot 26458 and disposed within
the interior region 26460 of the implant 26420, as shown in FIG.
141.
[0462] After the implant 26420 coupled to the guide member 26430,
the implant 26420 can be inserted within a body in the same manner
as described previously, using an insertion tool (not shown)
releasably coupled to the proximal end portion 26426 of the implant
26420. For example, the insertion tool can apply a longitudinal
force on a proximal end of the implant 26420 to move or advance the
implant 26420 within a body. This will in turn move or advance the
guide member 26430 coupled to the implant 26420. As with the
previous embodiments, the implant 26420 will be advanced along a
curved path defined by the guide member 26430. Once the implant
26420 is positioned at an implantation site, the guide member 26430
can be decoupled from the implant 26420 and removed from the body.
To decouple the guide member 26430 from the implant 26420, the
guide member 26430 is turned such that the key 26456 is
substantially aligned with the slot 26458. This will allow the
guide member 26430 to be moved out of the interior region 26460 of
the implant 26420 through the slot 26458, and removed from the
body. The insertion tool can also be removed as previously
described.
[0463] FIGS. 142 and 143 illustrate another embodiment of guide
member and implant. A medical device 26500 includes a guide member
26530 and an implant 26520. The implant 26520 and guide member
26530 are similar to the previous embodiments, except in this
embodiment, the guide member 26530 is coupled to the implant 26520
in a manner similar to the coupling between the implant 26220 and
insertion tool 26240 illustrated in FIG. 143. The implant 26520 has
a proximal end portion 26522 and a distal end portion 26524 that
defines an opening 26528. The distal end portion 26524 includes a
surface 26562 disposed within the opening 26528.
[0464] The guide member 26530 has a distal end portion 26534 that
includes a distal end 26538, and a proximal end portion 26532 that
can be received within the opening 26528. As shown in FIG. 143, the
implant 26520 can be advanced through a body B using an insertion
tool 26540 as previously described. As a force is applied by the
insertion tool 26540 and translated to a proximal end the implant
26520 in the direction of arrow D, the implant 26520 and the guide
member 26530 will be advanced along a path defined by the guide
member 26530. A longitudinal force is applied by the implant 26520
on the proximal end portion 26532 of the guide member 26530 to move
the implant 2620 in a direction toward the distal end 26538 of the
guide member 26530. This force will advance the guide member 26530
within the body, and maintain the position of the proximal end
portion 26532 of the guide member 26530 within the opening 26528 of
the implant 26520. In addition, internal walls of the implant 26520
that define the opening 26528 help maintain the position of the
proximal end portion 26532 of the guide member 26530 within the
opening 26528 of the implant 26520. After the implant 26520 is
positioned at a desired location within the body (e.g., between
adjacent spinous processes), and the distal tip 26538 of the guide
member 26530 has exited the body at a location B2, the guide member
26530 can be removed by pulling the guide member 26530 out through
the exit location 26554.
[0465] The guide members described above can be used in the
deployment of a variety of different types of implants. The guide
members can be configured to be releasably coupled to any of the
implants, extension limiting devices, extraction devices described
herein or with other devices not specifically described. For
example, a guide member as described herein can be configured to be
releasably coupled to an implant 6610 illustrated with references
to FIGS. 17-23. A distal end portion of the implant 6610 can be
configured with an opening that can receive a proximal end of a
guide member as described herein. Various different coupling
methods can also be included on an implant 6610, such as the key
and keyway coupling or the threaded coupling described above. Thus,
the implants and guide members described herein are merely example
embodiments to illustrate and described the use of a guide member
in the deployment of an implant within a body.
[0466] Further, the various coupling methods described herein to
releasably couple a guide member to a distal end portion of an
implant can also be used to couple an implant to an insertion tool.
Likewise, the various coupling methods described herein to
releasably couple an implant to an insertion tool can be used to
couple a guide member to an implant. For example, a guide member
and implant can each be configured to include a quick-connect
coupling to releasably couple the guide member to the implant. In
another example, a guide member can include one or more protrusions
configured to be received in one or more notches formed in the
distal end portion of the implant as described herein with
reference to the implant and insertion tool of FIGS. 15 and 16.
[0467] FIG. 144 is a flowchart of a method of using a guide member
to deliver an implant between spinous processes. At 26890, at least
a portion of a guide member as described herein is inserted
percutaneously into a body through at a first exterior location on
the body. A distal end portion of an implant is releasably coupled
to a proximal end portion of the guide member at 26891. The implant
can be coupled to the guide member either before or after the guide
member is inserted into the body. At 26892, an insertion tool is
releasably coupled to a proximal end portion of the implant. The
insertion tool can be coupled to the implant either before or after
the implant is coupled to the guide member. At 26893, the insertion
tool applies a force to the implant to move or advance the implant
such that the guide member is advanced within the body along a path
defined by the guide member. A trajectory of the path is defined by
the shape of the guide member. For example, the guide member can
have a curved shape and will define a curved path.
[0468] At 26894, the implant is positioned between adjacent bone
structures, such as between a superior and inferior spinous
process. The guide member is advanced such that a distal end of the
guide member exits the body at a second location. As stated
previously, the guide member can be advanced such that a distal end
of the guide member extends from the body at a second location
either before or after the implant has been inserted into the body.
Thus, the guide member can be so advanced simultaneously with the
positioning of the implant between adjacent bone structures. After
the implant is positioned between the bone structures, at 26895,
the guide member is decoupled from the implant and removed from the
body at a second location on the body. At 26896 the insertion tool
is decoupled from the implant and removed from the body.
[0469] FIG. 145 illustrates a device according to another
embodiment of the invention. A measurement device 26610 can be used
in conjunction with a procedure to deliver an implant between
adjacent bone structures, or a procedure to distract adjacent bone
structures, such as, for example, a procedure to distract adjacent
spinous processes as described herein. For example, the measurement
device 26610 can be used to measure the relative movement between
the adjacent bone structures being distracted and to measure the
amount of correction achieved by a distraction procedure. The
measurement device 26610 can be used independent of an implant or
other device used to distract the adjacent bone structures, and
without the use of an imaging device, such as a fluoroscopy device.
In addition, the measurement device 26610 is not limited to use in
conjunction with any particular type of distraction or extension
limiting device. The measurement device 26610 can also increase the
reliability and accuracy of a procedure to measure the amount of
distraction by reducing the potential variability of the interface
between, for example, a distraction device and an imaging device.
In addition, the measurement device 26610 extends outside of a
body, which allows a physician to visualize the physical correction
(e.g., distraction) being made to the bone structures external from
the patient rather than measuring the correction on an imaging
screen. Thus, the variability and/or error factor of the electronic
interface is eliminated.
[0470] As shown in FIG. 145. the measurement device 26610 includes
a first anchor member 26664 and a second anchor member 26666 that
can be coupled together such that the relative movement between the
first anchor member 26664 and the second anchor member 26666 can be
viewed and/or measured. The first anchor 26664 includes a first
portion 26668 that defines an opening 26670, and a second portion
26672 that can be driven or nailed to a bone structure. The second
anchor member 26666 includes a first portion 26674 that can be
received through the opening 26670 of the first anchor member
26664, and a second portion 26676 that can be driven or nailed to a
bone structure. The second portion 26672 of the first anchor member
26664, and the second portion 26676 of the second anchor member
26666 can alternatively include a threaded portion to screw or
threadedly couple each of the second portion 26672 and the second
portion 26676 to a bone structure.
[0471] The first portion 26674 of the second anchor member 26666
can move or slide relative to the first anchor member 26664 via the
opening 26670. The second anchor member 26666 also includes
markings 26678 along a longitudinal length of the first portion
26674. The markings 26678 can be measurement graduations and can be
used to determine an amount of movement between the first anchor
member 26664 and the second anchor member 26666 as described in
more detail below.
[0472] FIG. 146 illustrates an example use of the measurement
device 26610 to measure the distraction achieved between adjacent
spinous processes after insertion and/or use of a distraction
device such as an implant or distraction device as described
herein. Prior to the insertion of the distraction device, the
second portion 26672 of first anchor member 26664 is percutaneously
inserted through a first opening B1 of a body B, and removably
secured to a first spinous process S1 (e.g., nailed or driven into
the first spinous process S1). The first portion 26674 of the
second anchor member 26666 is disposed through the opening 26670 of
the first anchor member 26664, and the second portion 26676 of the
second anchor member 26666 is inserted through an opening B2 of the
body B, and removably secured to a second spinous process S2 (e.g.,
nailed or driven into the second spinous process S2). The
dashed-line illustration of a portion of the first anchor member
26664 and a portion of the second anchor member 26666 is shown to
indicate a position of the first spinous process S1 and the second
spinous process S2, before being distracted. A first measurement
can be taken using the markings 26678. For example, a first
measurement can be taken where the 26674 passes through the opening
26670 of the first anchor member 26664 as indicated at 26684, prior
to distracting the adjacent spinous processes.
[0473] A distraction device such as, for example, an implant or
distraction device described herein (not shown) can be placed
between the spinous process S1 and the spinous process S2. A force
F can be exerted on the spinous process S1 and the spinous process
S2 to move the first spinous process S1 and second spinous process
S2 apart a distance X. A second measurement can be taken where the
first portion 26674 of the second anchor member 26666 passes
through the opening 26670 of the first anchor member 26664 at
26686, after distracting the adjacent spinous processes. The
distance X can be calculated as the difference between the first
measurement and the second measurement.
[0474] FIG. 147 illustrates a measurement device according to
another embodiment. A measurement device 26710 is similar to a
template that can be used to determine the size of an implant that
is appropriate for implantation in the space between bone
structures. For example, the measurement device 26710 can be used
to measure the size of an implant to be placed between adjacent
spinous processes. Rather than approximating the size of an
appropriate implant when, for example, a patient is under
anesthesia and unable to provide feedback to the physician as to
whether their pain has been relieved, the measurement device 26710
can be used when the patient is awake. For example, an x-ray of a
patient's spine can be taken while the patient bends over. A
determination can be made as to the amount of distraction needed,
based on the level of pain relief the patient feels as the patient
bends over. The physician can place the measurement device 26710
adjacent an x-ray image, to measure the amount of distraction
necessary and the size of implant needed to be placed between the
adjacent spinous processes.
[0475] The measurement device 26710 is a substantially planar
device similar to a ruler or template. The measurement device 26710
can be formed of transparent material to allow the physician to see
an image, for example, from an x-ray, through. The measurement
device 26710 includes markings 26778, and defines multiple openings
26788. The markings 26778 are measurement graduations that can be
scaled to correspond to the type of image (e.g., x-ray) being used
during the measurement process. The openings 26788 can be sized,
for example, to correspond to various sizes of interspinous
implants. The scale of the markings 26788 to the size of the
openings 26788 can vary depending on the particular imaging device.
For example, the markings 26788 used to measure the image can be a
1:1 scale to the dimensions used for the openings 26788. For
example, for a 1:1 scale, 10 graduations of the markings 26788
equals a 10 mm diameter opening 26788. Other scales can
alternatively be used.
[0476] FIG. 148 illustrates an example use of the measurement
device 26710. The measurement device 26710 is placed adjacent to,
or in contact with an image I, which is a side view of a portion of
a patient's spine. A visual of the spinal components can be viewed
through the measurement device 26710. To determine a size of an
implant needed to be placed between a spinous process S1 and a
spinous process S2, a distance between the spinous processes is
measured using the markings 26778. The size of implant appropriate
for implantation is then determined by the opening 26788 that
corresponds to the measurement of the markings 26778. In the
example shown in FIG. 148, a distance between the spinous processes
S1 and S2 is approximately 6 graduations as indicated on markings
26778, and the appropriate implant size would be 8 mm as indicated
by the opening 26788 that corresponds to the 6 mm graduation.
[0477] FIGS. 149-152 are schematic illustrations of an implant
27100 according to an embodiment of the invention in a first
configuration, a second configuration, a third configuration and a
fourth configuration, respectively. The implant 27100 includes a
support member 27102, a first retention member 27112 and a second
retention member 27110. The support member 27102 has a first end
portion 27106, a second end portion 27104 and an outer surface
27116. As shown in FIGS. 151 and 152, at least a portion of the
outer surface 27116 is configured to be disposed between a first
spinous process SP1 and a second spinous process SP2.
[0478] The first retention member 27112 has a first end portion
27130, a second end portion 27132 and defines a longitudinal axis
L.sub.A1. The first end portion 27130 of the first retention member
27112 has an inner surface 27136 and an outer surface 27137
opposite the inner surface 27136. Similarly, the second end portion
27132 of the first retention member 27112 has an inner surface
27138 and an outer surface 27139 opposite the inner surface 27138.
Although the inner surface 27136 of the first end portion 27130 and
the inner surface 27138 of the second end portion 27132 are shown
as forming a continuous, co-planar surface, in other embodiments,
the inner surface 27136 of the first end portion 27130 can be
discontinuous or in a plane different than the inner surface 27138
of the second end portion 27132. Similarly, in some embodiments,
the outer surface 27137 of the first end portion 27130 can be
discontinuous or in a plane different than the outer surface 27139
of the second end portion 27132.
[0479] The second retention member 27110 has a first end portion
27140, a second end portion 27142 and defines a longitudinal axis
L.sub.A2. The first end portion 27140 of the second retention
member 27110 has an inner surface 27146 and an outer surface 27147
opposite the inner surface 27146. Similarly, the second end portion
27142 of the second retention member 27110 has an inner surface
27148 and an outer surface 27149 opposite the inner surface 27148.
Although the inner surface 27146 of the first end portion 27140 and
the inner surface 27148 of the second end portion 27142 are shown
as forming a continuous, co-planar surface, in other embodiments,
the inner surface 27146 of the first end portion 27140 can be
discontinuous or in a plane different than the inner surface 27148
of the second end portion 27142. Similarly, in some embodiments,
the outer surface 27147 of the first end portion 27140 can be
discontinuous or in a plane different than the outer surface 27149
of the second end portion 27142.
[0480] The first retention member 27112 is slidably coupled to the
first end portion 27106 of the support member 27102. As indicated
by the arrow PP in FIG. 152, the first retention member 27112 can
translate along its longitudinal axis L.sub.A1 between a first
position (FIGS. 149-151) and a second position (FIG. 152). When the
first retention member 27112 is in the first position, the first
end portion 27130 is spaced apart from the support member 27102 and
the second end portion 27132 is adjacent the first end portion
27106 of the support member 27102. Moreover, as described in more
detail herein, when the first retention member 27112 is in the
first position, the first end portion 27130 can contact and/or
engage the first spinous process SP1 (or its associated surrounding
tissue) to limit lateral movement of the support member 27102 along
the lateral axis L.sub.L and relative to the adjacent spinous
processes SP1 and SP2. When the first retention member 27112 is in
the second position, the first end portion 27130 is spaced apart
from the support member 27102 and the second end portion 27132 is
spaced apart from the support member 27102. Moreover, as described
in more detail herein, when the first retention member 27112 is in
the second position, the first end portion 27130 can contact and/or
engage the first spinous process SP1 (or its associated surrounding
tissue) and the second end portion 27132 can contact and/or engage
the second spinous process SP2 (or its associated surrounding
tissue). In this manner, when the first retention member 27112 is
in its second position, the first retention member 27112 can limit
lateral movement of the support member 27102 along the lateral axis
L.sub.L and relative to the adjacent spinous processes SP1 and
SP2.
[0481] Similarly, the second retention member 27110 is slidably
coupled to the second end portion 27104 of the support member
27102. As indicated by the arrow QQ in FIG. 152, the second
retention member 27110 can translate along its longitudinal axis
L.sub.A2 between a first position (FIGS. 149-151) and a second
position (FIG. 152). When the second retention member 27112 is in
the first position, the first end portion 27140 is spaced apart
from the support member 27102 and the second end portion 27142 is
adjacent the second end portion 27104 of the support member 27102.
Moreover, as described in more detail herein, when the second
retention member 27110 is in the first position, the first end
portion 27140 can contact and/or engage the second spinous process
SP2 (or its associated surrounding tissue) to limit lateral
movement of the support member 27102 along the lateral axis L.sub.L
and relative to the adjacent spinous processes SP1 and SP2. When
the second retention member 27110 is in the second position, the
first end portion 27140 is spaced apart from the support member
27102 and the second end portion 27142 is spaced apart from the
support member 27102. Moreover, as described in more detail herein,
when the second retention member 27110 is in the second position,
the first end portion 27140 can contact and/or engage the second
spinous process SP2 (or its associated surrounding tissue) and the
second end portion 27142 can contact and/or engage the first
spinous process SP1 (or its associated surrounding tissue). In this
manner, when the second retention member 27110 is in its second
position, the second retention member 27110 can limit lateral
movement of the support member 27102 along the lateral axis L.sub.L
and relative to the adjacent spinous processes SP1 and SP2.
[0482] In use, the adjacent spinous processes SP1 and SP2 can be
distracted prior to inserting the implant 27100 into the patient.
An access passageway can be defined to allow insertion of the
implant 27100. The passageway can have any suitable shape and can
be formed by any suitable method, as discussed herein. After the
access passageway is defined, the implant 27100 can be inserted
percutaneously along a lateral access passageway, as shown by the
arrow NN in FIG. 149. As shown in FIG. 149, during insertion, the
implant 27100 is placed in a first configuration in which the first
retention member 27112 is in the first position, the second
retention member 27110 is in the first position, the longitudinal
axis L.sub.A1 of the first retention member 27112 is substantially
parallel to the lateral axis L.sub.L, and the longitudinal axis
L.sub.A2 of the second retention member 27110 is substantially
parallel to the lateral axis L.sub.L. The overall length of the
implant 27100 (i.e., the sum of lengths L.sub.1, L.sub.2 and
L.sub.3 as shown in FIG. 151) is such that the implant 27100 can be
disposed between the first spinous process SP1 and the second
spinous process SP2 when the implant is in the first
configuration.
[0483] Although the implant 27100 is described as being inserted
after an access passageway is defined, in some embodiments, an
access passageway can be defined by the implant when it is being
inserted. For example, in some embodiments, the first end portion
27130 of the first retention member 27112 can include a sharp tip
suitable for defining a passageway. Similarly, in some embodiments,
portions of the retention members 27112, 27110 and/or the support
member 27102 can be tapered such that a passageway can be defined
when the implant 27100 is being inserted.
[0484] When the implant 27100 is between the first spinous process
SP1 and the second spinous process SP2, the implant 27100 can be
rotated into the second configuration. As shown by the arrow OO in
FIG. 150, the implant 27100 can be rotated relative to the adjacent
spinous processes SP1 and SP2 about an axis substantially normal to
a mid-line axis L.sub.M defined by the spinal column. The diagonal
dimension D across the support member 27102 and including a portion
of the first retention member 27112 and the second retention member
27110 is such that the implant 27100 can be disposed between the
first spinous process SP1 and the second spinous process SP2 when
the implant is in the second configuration. Said another way, the
diagonal dimension D is sized such that the implant 27100 can be
rotated as shown in FIG. 150. Although the diagonal dimension D is
shown as being less than the spacing between the first spinous
process SP1 and the second spinous process SP2 such that the
implant 27100 can be rotated without contacting the first spinous
process SP1 and/or the second spinous process SP2, in other
embodiments, the diagonal dimension D can be greater than the
spacing between the adjacent spinous processes SP1 and SP2. In such
embodiments, the implant can distract the adjacent spinous
processes SP1 and SP2 when in the second configuration (i.e., when
rotating relative to the adjacent spinous processes SP1 and
SP2).
[0485] As shown in FIG. 151, the implant 27100 can be rotated
relative to the adjacent spinous processes SP1 and SP2
approximately ninety degrees into the third configuration (i.e.,
the implant can be moved from the first configuration shown in FIG.
149 to the third configuration shown in FIG. 151). When the implant
27100 is in the third configuration, the first retention member
27112 is in its first position and the second retention member
27110 is in its first position. Additionally, when the implant
27100 is in the third configuration, the inner surface 27136 of the
first end portion 27130 of the first retention member 27112 is
disposed adjacent the first spinous process SP1. Said another way,
when the implant 27100 is in the third configuration, the inner
surface 27136 of the first end portion 27130 of the first retention
member 27112 is between the outer surface 27137 of the first end
portion 27130 of the first retention member 27112 and the first
spinous process SP1. In some embodiments, the inner surface 27136
of the first end portion 27130 can substantially contact a portion
of the first spinous process SP1 (either directly or indirectly
through surrounding tissue) when the implant 27100 is in the third
configuration.
[0486] Similarly, when the implant 27100 is in the third
configuration, the inner surface 27146 of the first end portion
27140 of the second retention member 27110 is disposed adjacent the
second spinous process SP2. Said another way, when the implant
27100 is in the third configuration, the inner surface 27146 of the
first end portion 27140 of the second retention member 27110 is
between the outer surface 27147 of the first end portion 27140 of
the second retention member 27110 and the second spinous process
SP2. In some embodiments, the inner surface 27146 of the first end
portion 27140 can substantially contact a portion of the second
spinous process SP2 (either directly or indirectly through
surrounding tissue) when the implant 27100 is in the third
configuration.
[0487] After the implant 27100 is placed in the third
configuration, the first retention member 27112 can be moved along
its longitudinal axis L.sub.A1 from the first position to the
second position, as indicated by the arrow PP in FIG. 152. Said
another way, the first retention member 27112 can be moved from the
first position to the second position along an axis substantially
parallel to the mid-line axis L.sub.M. Similarly, the second
retention member 27110 can be moved along its longitudinal axis
L.sub.A2 from the first position to the second position, as
indicated by the arrow QQ in FIG. 152. Said another way, the second
retention member 27110 can be moved from the first position to the
second position along an axis substantially parallel to the
mid-line axis L.sub.M. As indicated by the arrows PP and QQ, the
first retention member 27112 can be moved in a first direction
(downward) and the second retention member 27110 can be moved in a
second direction (upward), opposite the first direction. In this
manner, the implant can be placed into the fourth configuration, as
shown in FIG. 152.
[0488] When the implant 27100 is in the fourth configuration, the
first end portion 27130 of the first retention member 27112 is
spaced apart from the support member 27102 and the second end
portion 27132 of the first retention member 27112 is spaced apart
from the support member 27102. Moreover, when the implant 27100 is
in the fourth configuration, the first end portion 27130 is
disposed adjacent the first spinous process SP1 and the second end
portion 27132 is disposed adjacent the second spinous process SP2.
Said another way, when the implant 27100 is in the fourth
configuration, the inner surface 27136 of the first end portion
27130 of the first retention member 27112 is between the outer
surface 27137 of the first end portion 27130 of the first retention
member 27112 and the first spinous process SP1. Similarly, the
inner surface 27138 of the second end portion 27132 of the first
retention member 27112 is between the outer surface 27139 of the
second end portion 27132 of the first retention member 27112 and
the second spinous process SP2. In this manner, when the implant
27100 is in the fourth configuration, the first retention member
27112 can limit lateral movement of the support member 27102 along
the lateral axis L.sub.L and relative to the adjacent spinous
processes SP1 and SP2. In some embodiments, the inner surface 27136
of the first end portion 27130 and/or the inner surface 27138 of
the second end portion 27132 can substantially contact a portion of
the first spinous process SP1 and/or the second spinous process
SP2, respectively (either directly or indirectly through
surrounding tissue) when the implant 27100 is in the fourth
configuration.
[0489] When the implant 27100 is in the fourth configuration, the
first end portion 27140 of the second retention member 27110 is
spaced apart from the support member 27102 and the second end
portion 27142 of the second retention member 27110 is spaced apart
from the support member 27102. Moreover, when the implant 27100 is
in the fourth configuration, the first end portion 27140 is
disposed adjacent the second spinous process SP2 and the second end
portion 27142 is disposed adjacent the first spinous process SP1.
Said another way, when the implant 27100 is in the fourth
configuration, the inner surface 27146 of the first end portion
27140 of the second retention member 27110 is between the outer
surface 27147 of the first end portion 27140 of the second
retention member 27110 and the second spinous process SP2.
Similarly, the inner surface 27148 of the second end portion 27142
of the second retention member 27110 is between the outer surface
27149 of the second end portion 27142 of the second retention
member 27110 and the first spinous process SP1. In this manner,
when the implant 27100 is in the fourth configuration, the second
retention member 27110 can limit lateral movement of the support
member 27102 along the lateral axis L.sub.L and relative to the
adjacent spinous processes SP1 and SP2. In some embodiments, the
inner surface 27146 of the first end portion 27140 and/or the inner
surface 27148 of the second end portion 27142 can substantially
contact a portion of the second spinous process SP2 and/or the
first spinous process SP1, respectively (either directly or
indirectly through surrounding tissue) when the implant 27100 is in
the fourth configuration.
[0490] If or when it is desirable to change the position of the
implant 27100 and/or remove the implant 27100, the first retention
member 27112 can be moved back to its first position and the second
retention member 27110 can be moved back to its first position,
thereby allowing the implant 27100 to be rotated (in direction
opposite from that indicated by the arrow OO in FIG. 150) to place
the implant 27100 back in the second configuration. Once the
implant 27100 is in the second configuration, the implant 27100 can
be repositioned and/or removed. If or when the implant 27100 is
repositioned as desired, the implant can be moved to the fourth
configuration, as described above.
[0491] In some embodiments, the first retention member 27112 and
the second retention member 27110 can be moved relative to the
support member 27102 serially. In other embodiments, the first
retention member 27112 and the second retention member 27110 can be
moved relative to the support member 27102 simultaneously. In yet
other embodiments, only one of the first retention member 27112 or
the second retention member 27110 can be moved relative to the
support member 27102.
[0492] In some embodiments, the first retention member 27112 can be
temporarily maintained in its first position and/or its second
position by a locking mechanism as shown and described above in
connection with other embodiments (see e.g., FIGS. 95-99).
Similarly, in some embodiments, the first retention member 27112
can be biased in its first position and/or its second position by a
biasing member as shown and described above in connection with
other embodiments (see e.g., FIGS. 118-123). In some embodiments,
the second retention member 27110 can be temporarily maintained in
its first position and/or its second position by a locking
mechanism as shown and described above in connection with other
embodiments (see e.g., FIGS. 95-99). Similarly, in some
embodiments, the second retention member 27110 can be biased in its
first position and/or its second position by a biasing member as
shown and described above in connection with other embodiments (see
e.g., FIGS. 118-123).
[0493] Although the implant 27100 is shown and described without
reference to any specific dimensions, the implant 27100 can have
any suitable size to be disposed between the adjacent spinous
processes SP1 and SP2 as described above. In some embodiments, for
example, the implant 27100 can be sized such that the diagonal
dimension D is less than the distance between the first spinous
process SP1 and the second spinous process SP2 such that the
implant 27100 can be rotated without substantially contacting the
first spinous process SP1 and/or the second spinous process SP2. In
other embodiments, the implant 27100 can be sized such that the
diagonal dimension D can be greater than the spacing between the
adjacent spinous processes SP1 and SP2.
[0494] Referring to the dimensions shown in FIG. 151, in some
embodiments, for example, the length L.sub.3 of the support member
27102 can be between 5 mm and 16 mm. In some embodiments, the
length L.sub.3 of the support member 27102 can be approximately 8
mm. In some embodiments, the length L.sub.1 of the first retention
member 27112 can be between 1 mm and 4 mm. In some embodiments, the
length L.sub.1 of the first retention member 27112 can be
approximately 2 mm. Similarly, in some embodiments, the length
L.sub.2 of the second retention member 27110 can be between 1 mm
and 4 mm. In some embodiments, the length L.sub.2 of the second
retention member 27110 can be approximately 2 mm.
[0495] In some embodiments, the height H.sub.3 of the support
member 27102 can be between 6 mm and 16 mm. In some embodiments,
the height H.sub.3 of the support member 27102 can be approximately
8 mm. In some embodiments, the height H.sub.1 of the first
retention member 27112 can be between 14 mm and 32 mm. In some
embodiments, the height H.sub.1 of the first retention member 27112
can be approximately 18 mm. Similarly, in some embodiments, the
height H.sub.2 of the second retention member 27110 can be between
14 mm and 32 mm. In some embodiments, the height H.sub.2 of the
second retention member 27110 can be approximately 18 mm. Although
the height H.sub.1 and the height H.sub.2 are shown as being
substantially equal, in other embodiments, the height H.sub.1 of
the first retention member 27112 can be different than the height
H.sub.2 of the second retention member 27110. Similarly, although
the first retention member 27112 and the second retention member
27110 are shown as being positioned symmetrically about the lateral
axis L.sub.L when in their respective second positions (see FIG.
152), in some embodiments, the first retention member 27112 and/or
the second retention member 27110 can be positioned asymmetrically
about the lateral axis L.sub.L when in their respective second
positions.
[0496] Although the first retention member 27112 and the second
retention member 27110 are shown as being coupled to and disposed
outside of the support member 27102, in some embodiments, the first
retention member 27112 and/or the second retention member 27110 can
be arranged such that at least a portion thereof is disposed within
the support member 27102. For example, in some embodiments, a
support member can define an opening in which a portion of a first
retention member and/or a second retention member is disposed. In
such embodiments, the opening of the support member can be, for
example, a slot at an end portion of the support member configured
to receive a portion of the first retention member and/or the
second retention member. In this manner, the first retention member
and/or the second retention member can translate within the slot
between a first position and a second position, as described above.
For example, in some embodiments, an end portion of a retention
member can be disposed within the support member (e.g., within the
slot defined by the support member) when the retention member is in
the first position. The end portion of the retention member can be
disposed outside of the support member when the retention member is
in the second position.
[0497] Although the implant 27100 is shown and described above as
being rotated relative to the adjacent spinous processes SP1 and
SP2 approximately ninety degrees into the third configuration, in
some embodiments, an implant can be rotated any suitable amount to
during insertion. For example, in some embodiments, an implant can
be rotated between 45 degrees and 135 degrees. In other
embodiments, an implant can be rotated between 5 degrees and 90
degrees. In yet other embodiments, an implant can be rotated
between 5 and 175 degrees. Similarly, in some embodiments, an
implant can be rotated incrementally when a retention member is
translated relative to a support member of the implant.
[0498] Although the implant 27100 is shown and described as
including a first retention member 27112 and a second retention
member 27110, in other embodiments and implant can include only one
retention member. For example, FIGS. 153-156 are schematic
illustrations of an implant 27200 according to an embodiment of the
invention in a first configuration, a second configuration, a third
configuration and a fourth configuration, respectively. The implant
27200 includes a support member 27202 and a retention member 27212.
The support member 27202 has a first end portion 27206, a second
end portion 27204 and an outer surface 27216. The support member
27202 is tapered such that a size of the first end portion 27206
(e.g., the height H.sub.1 as shown in FIG. 156) is less than a size
of the second end portion 27204 (e.g., the height H.sub.2 as shown
in FIG. 156). In this manner, the outer surface 27216 of the
support member 27202 includes a tapered portion 27217. As shown in
FIGS. 155 and 156, at least a portion of the outer surface 27216 is
configured to be disposed between a first spinous process SP1 and a
second spinous process SP2.
[0499] The retention member 27212 has a first end portion 27230, a
second end portion 27232 and defines a longitudinal axis L.sub.A.
The first end portion 27230 of the retention member 27212 has an
inner surface 27236 and an outer surface 27237 opposite the inner
surface 27236. Similarly, the second end portion 27232 of the
retention member 27212 has an inner surface 27238 and an outer
surface 27239 opposite the inner surface 27238. Although the inner
surface 27236 of the first end portion 27230 and the inner surface
27238 of the second end portion 27232 are shown as forming a
continuous, co-planar surface, in other embodiments, the inner
surface 27236 of the first end portion 27230 can be discontinuous
or in a plane different than the inner surface 27238 of the second
end portion 27232. Similarly, in some embodiments, the outer
surface 27236 of the first end portion 27230 can be discontinuous
or in a plane different than the outer surface 27238 of the second
end portion 27232.
[0500] The retention member 27212 is slidably coupled to the first
end portion 27206 of the support member 27202. As indicated by the
arrow RR in FIG. 153, the retention member 27212 can translate
along its longitudinal axis L.sub.A between a first position (FIGS.
153-155) and a second position (FIG. 156). When the retention
member 27212 is in the first position, the first end portion 27230
is spaced apart from the support member 27202 and the second end
portion 27232 is adjacent the first end portion 27206 of the
support member 27202. Moreover, as described in more detail herein,
when the retention member 27212 is in the first position, the first
end portion 27230 can contact and/or engage the first spinous
process SP1 (either directly or indirectly through its surrounding
tissue) to limit lateral movement of the support member 27202 along
the lateral axis L.sub.L and relative to the adjacent spinous
processes SP1 and SP2. When the retention member 27212 is in the
second position, the first end portion 27230 is spaced apart from
the support member 27202 and the second end portion 27232 is spaced
apart from the support member 27202. Moreover, as described in more
detail herein, when the retention member 27212 is in the second
position, the first end portion 27230 can contact and/or engage the
first spinous process SP1 (either directly or indirectly through
its surrounding tissue) and the second end portion 27232 can be
contact and/or engage the second spinous process SP2 (either
directly or indirectly through its surrounding tissue). In this
manner, when the retention member 27212 is in its second position,
the retention member 27212 can limit lateral movement of the
support member 27202 along the lateral axis L.sub.L and relative to
the adjacent spinous processes SP1 and SP2.
[0501] In use, the implant 27200 can be inserted percutaneously
along a lateral access passageway, as shown by the arrow RR in FIG.
153. As shown in FIG. 153, during insertion, the implant 27200 is
placed in a first configuration in which the retention member 27212
is in the first position and the longitudinal axis L.sub.A of the
retention member 27212 is substantially parallel to the lateral
axis L.sub.L. As described above, the implant 27200 is sized such
that the implant 27200 can be disposed between the first spinous
process SP1 and the second spinous process SP2 when the implant is
in the first configuration. In other embodiments, the implant 27200
can be sized such that the implant 27200 can distract the adjacent
spinous processes SP1 and SP2 during insertion.
[0502] When the implant 27200 is between the first spinous process
SP1 and the second spinous process SP2, the implant 27200 can be
rotated into the second configuration. As shown by the arrow SS in
FIG. 154, the implant 27200 can be rotated relative to the adjacent
spinous processes SP1 and SP2 about an axis substantially normal to
a mid-line axis L.sub.M defined by the spinal column. The diagonal
dimension D across the support member 27202 and including a portion
of the retention member 27212 is such that the implant 27200 can be
disposed between the first spinous process SP1 and the second
spinous process SP2 when the implant is in the second
configuration. Said another way, the diagonal dimension D is sized
such that the implant 27200 can be rotated as shown in FIG.
154.
[0503] As shown in FIG. 155, the implant 27200 can be rotated
relative to the adjacent spinous processes SP1 and SP2
approximately ninety degrees into the third configuration. When the
implant 27200 is in the third configuration, the retention member
27212 is in its first position and the longitudinal axis L.sub.A of
the retention member 27212 is substantially parallel to the
mid-line axis L.sub.M. Additionally, when the implant 27200 is in
the third configuration, the inner surface 27236 of the first end
portion 27230 of the retention member 27212 can contact and/or
engage the first spinous process SP1, either directly or through
surrounding tissue. Said another way, when the implant 27200 is in
the third configuration, the inner surface 27236 of the first end
portion 27230 of the retention member 27212 is between the outer
surface 27237 of the first end portion 27230 of the retention
member 27212 and the first spinous process SP1.
[0504] Moreover, when the implant 27200 is in the third
configuration, the tapered portion 27217 of the outer surface 27216
of the support member 27202 is adjacent the first spinous process
SP1 and/or the second spinous process SP2. In some embodiments, the
tapered portion 27217 of the outer surface 27216 can substantially
contact a portion of the first spinous process SP1 and/or the
second spinous process SP2 (either directly or indirectly through
surrounding tissue) when the implant 27200 is in the third
configuration.
[0505] After the implant 27200 is placed in the third
configuration, the retention member 27212 can be moved along its
longitudinal axis L.sub.A from the first position to the second
position, as indicated by the arrow TT in FIG. 156. Said another
way, the retention member 27212 can be moved from the first
position to the second position along an axis substantially
parallel to the mid-line axis L.sub.M. In this manner, the implant
can be placed into the fourth configuration, as shown in FIG.
156.
[0506] When the implant 27200 is in the fourth configuration, the
first end portion 27230 of the retention member 27212 is spaced
apart from the support member 27202 and the second end portion
27232 of the retention member 27212 is spaced apart from the
support member 27202. Moreover, when the implant 27200 is in the
fourth configuration, the first end portion 27230 can contact
and/or engage the first spinous process SP1 and the second end
portion 27232 can contact and/or engage the second spinous process
SP2. Said another way, when the implant 27200 is in the fourth
configuration, the inner surface 27236 of the first end portion
27230 of the retention member 27212 is between the outer surface
27237 of the first end portion 27230 of the retention member 27212
and the first spinous process SP1. Similarly, the inner surface
27238 of the second end portion 27232 of the retention member 27212
is between the outer surface 27239 of the second end portion 27232
of the retention member 27212 and the second spinous process SP2.
Additionally, when the implant 27200 is in the fourth
configuration, the tapered portion 27217 of the outer surface 27216
remains between the first spinous process SP1 and the second
spinous process SP2. In this manner, when the implant 27200 is in
the fourth configuration, the retention member 27212 and/or the
tapered portion 27217 can limit lateral movement of the support
member 27202 along the lateral axis L.sub.L and relative to the
adjacent spinous processes SP1 and SP2.
[0507] Although the support member 27206 is shown and described as
being asymmetrically tapered, in other embodiments, a support
member can be symmetrically tapered. Said another way, although the
portion of the outer surface 27216 adjacent the first spinous
process SP1 (see FIGS. 155 and 156) is shown as having a different
amount of taper than the tapered portion 27217, in other
embodiments, the portion of the support member adjacent the first
spinous process SP1 can have the same taper as the portion of the
support member adjacent the second spinous process SP2.
[0508] Although the support member 27206 is shown and described as
being tapered linearly, in other embodiments, a support member can
have a curved taper. Similarly, in some embodiments, an end portion
of a retention member can be tapered. For example, in some
embodiments an end portion of a retention member can include a
pointed tip such that the implant can define its own access
passageway when inserted into the body.
[0509] FIG. 157 is a flow chart illustrating a method 27300
according to an embodiment of the invention. The method includes
inserting at least a portion of an implant between a first spinous
process and a second spinous process, 27304. The implant includes a
support member and a retention member movably coupled to the
support member. The implant can be any suitable implant of the
types shown and described above, such as for example, the implant
27100.
[0510] In some embodiments, the inserting can include inserting the
implant percutaneously via a lateral access path. In some
embodiments, the inserting can include positioning the implant such
that a longitudinal axis of the retention member is substantially
parallel to a lateral axis defined between the spinous processes.
In some embodiments, the implant can be inserted using a curved
tool and/or a guide member, as described herein. In some
embodiments, the method can include optionally distracting the
adjacent spinous processes before the disposing, 27302.
[0511] The implant is then rotated relative to the first spinous
process and the second spinous process about an axis substantially
normal to a mid-line axis defined by a spinal column, 27306. In
some embodiments, for example, the implant is rotated approximately
ninety degrees relative to the first spinous process and the second
spinous process. In some embodiments, for example, the implant is
rotated such that an inner surface of an end portion of the
retention member is between an outer surface of the end portion of
the retention member and the first spinous process.
[0512] The retention member is translated relative to the support
member, 27308. In some embodiments, the retention member is
translated relative to the support member in a direction
substantially parallel to the mid-line axis defined by a spinal
column. In some embodiments, the retention member is translated
relative to the support member along the longitudinal axis of the
retention member. In some embodiments, the retention member is
translated such that an inner surface of a second end portion of
the retention member is between an outer surface of the second end
portion of the retention member and the second spinous process.
[0513] In some embodiments, the method can include optionally
maintaining a position of the retention member relative to the
support member, 27310. The position of the retention member can be
maintained, for example, by moving a locking member such that a
portion of the locking member is received within a recess defined
by the support member and/or the retention member, as described
above.
[0514] FIG. 158 is a flow chart illustrating a method 27400
according to an embodiment of the invention. The method includes
inserting an implant having a first member, a second member and a
third member such that at least a portion of the first member is
disposed between a first spinous process and a second spinous
process, 27404. The implant can be any suitable implant of the
types shown and described above, such as for example, the implant
27100.
[0515] In some embodiments, the inserting can include inserting the
implant percutaneously via a lateral access path. In some
embodiments, the inserting can include positioning the implant such
that a longitudinal axis of the retention member is substantially
parallel to a lateral axis defined between the spinous processes.
In some embodiments, the implant can be inserted using a curved
tool and/or a guide member, as described herein. In some
embodiments, the method can include optionally distracting the
adjacent spinous processes before the disposing, 27402.
[0516] The implant is then rotated relative to the first spinous
process and the second spinous process such that an inner surface
the second member is between an outer surface the second member and
the first spinous process and an inner surface of the third member
is between an outer surface of the third member and the second
spinous process, 27406. In some embodiments, for example, the
implant is rotated about an axis substantially normal to a mid-line
axis defined by a spinal column. In some embodiments, for example,
the implant is rotated approximately ninety degrees relative to the
first spinous process and the second spinous process.
[0517] The second member is translated relative to the first
member, 27408. In some embodiments, the second member is translated
along a longitudinal axis of the second member substantially
parallel to the mid-line axis defined by a spinal column. In some
embodiments, the second member is translated such that an inner
surface of the second member is between an outer surface of the
second member and the second spinous process.
[0518] In some embodiments, the method optionally includes
translating the third member relative to the first member, 27410.
In some embodiments, the third member is translated along a
longitudinal axis of the third member substantially parallel to the
mid-line axis. In some embodiments, the third member is translated
such that an inner surface of the third member is between an outer
surface of the third member and the first spinous process.
[0519] In some embodiments, the method can include optionally
maintaining a position of the second member and/or the third member
relative to the support member, 27412. The position of the second
member and/or the third member can be maintained by a locking
mechanism, as described above.
[0520] The various implants, deployment/insertion tools, and guide
members described herein can be constructed with various
biocompatible materials such as, for example, titanium, titanium
alloyed, surgical steel, biocompatible metal alloys, stainless
steel, plastic, polyetheretherketone (PEEK), carbon fiber,
ultra-high molecular weight (UHMW) polyethylene, biocompatible
polymeric materials, etc. The material of a central portion of the
implant can have, for example, a compressive strength similar to or
higher than that of bone. In one embodiment, the central portion of
the implant, which is placed between the two adjacent spinous
processes, is configured with a material having an elastic modulus
higher than the elastic modulus of the bone, which forms the
spinous processes. In another embodiment, the central portion of
the implant is configured with a material having a higher elastic
modulus than the materials used to configure the distal and
proximal portions of the implant. For example, the central portion
of the implant may have an elastic modulus higher than bone, while
the proximal and distal portions have a lower elastic modulus than
bone. In yet another embodiment, where the implant is configured
with an outer shell and an inner core. The outer shell can be
configured with material having a higher elastic modulus than the
inner core (e.g., outer shell is made with titanium alloyed, while
the inner core is made with a polymeric material). Alternatively,
the outer shell can be configured with a material having a lower
elastic modulus than the inner core (e.g., the outer shell is made
with a polymeric material while the inner core is made with a
titanium alloyed material).
[0521] While various embodiments of the invention have been
described above, it should be understood that they have been
presented by way of example only, and not limitation. Where methods
and steps described above indicate certain events occurring in
certain order, those of ordinary skill in the art having the
benefit of this disclosure would recognize that the ordering of
certain steps may be modified and that such modifications are in
accordance with the variations of the invention. Additionally,
certain of the steps may be performed concurrently in a parallel
process when possible, as well as performed sequentially as
described above. Thus, the breadth and scope of the invention
should not be limited by any of the above-described embodiments,
but should be defined only in accordance with the following claims
and their equivalents. While the invention has been particularly
shown and described with reference to specific embodiments thereof,
it will be understood that various changes in form and details may
be made.
[0522] For example, although the embodiments above are primarily
described as being spinal implants configured to be positioned
between adjacent spinous processes, in alternative embodiments, the
implants are configured to be positioned adjacent any bone, tissue
or other bodily structure where it is desirable to maintain spacing
while preventing axial or longitudinal movement of the implant.
[0523] Although the medical devices are shown and described as
including an implant and/or a deployment tool, in some embodiments
a kit can include any number of implants and/or any number of
deployment tools and/or any number of guide members as described
above. For example, a kit can include an implant and two deployment
tools, one deployment tool configured to be used to move the
implant from a collapsed configuration to an expanded
configuration, and another deployment tool configured to be used to
move the implant from the expanded configuration to the collapsed
configuration. Alternatively, a kit can include a single deployment
tool have multiple engaging portions as described herein, that can
be releasably coupled to an elongate member of a deployment tool.
For example, one type or style of engaging portion can be used to
move the implant from a collapsed configuration to an expanded
configuration, and another type or style of engaging portion can be
used to move the implant from the expanded configuration to the
collapsed configuration. The kit can include engaging portions
having one of a variety of different shapes and sizes, such that a
user can select a particular engaging portion(s) for use in a
particular application. In another example, a kit can include more
than one guide member, each having a different length to
accommodate different needs and/or uses.
[0524] Similarly, although various embodiments have been described
as having particular features and/or combinations of components,
other embodiments are possible having a combination of any features
and/or components from any of embodiments as discussed above. For
example, one such embodiment includes an implant having a locking
mechanism of the type shown and described above with reference to
FIGS. 95-99 and two retention members configured to rotate about an
axis of rotation substantially normal to a longitudinal axis of the
implant, as shown and described above with reference to FIGS.
124-127.
[0525] Although various implants have been shown and described
above as having a first configuration and a second configuration,
in some embodiments, an implant can include three or more
configurations. For example, in some embodiments, an implant can
have a first configuration, in which the implant can be inserted
between the spinous processes unimpeded by a retention member of
the implant, a second configuration, in which lateral movement of
the implant is limited by the retention member and a third
configuration in which the implant can move in one lateral
direction, but not the other.
[0526] Similarly, in some embodiments, a deployment tool, an
expansion device and/or an insertion tool can be configured to
perform any combination of functions described herein. For example,
in some embodiments, a deployment tool, an expansion devices and/or
an insertion tool can be configured to insert a spinal implant into
a body, move a spinal implant between a retracted configuration and
an expanded configuration within a body, reposition a spinal
implant within the body and/or remove a spinal implant within the
body. In some embodiments, a deployment tool, an expansion device
and/or an insertion tool can be configured to perform only a single
function, such as, for example, removing a spinal implant from
body. In other embodiments, a kit can include a deployment tool, an
expansion device and/or an insertion tool along with various
implements so that the deployment tool, expansion device and/or
insertion tool can be re-configured to perform any combination of
functions described herein.
* * * * *