U.S. patent application number 14/216893 was filed with the patent office on 2014-09-18 for expandable vertebral body replacement device, system, and methods.
This patent application is currently assigned to SPECTRUM SPINE IP HOLDINGS, LLC. The applicant listed for this patent is John E. Pendleton, James C. Robinson. Invention is credited to John E. Pendleton, James C. Robinson.
Application Number | 20140277510 14/216893 |
Document ID | / |
Family ID | 51531338 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140277510 |
Kind Code |
A1 |
Robinson; James C. ; et
al. |
September 18, 2014 |
EXPANDABLE VERTEBRAL BODY REPLACEMENT DEVICE, SYSTEM, AND
METHODS
Abstract
An expandable vertebral body replacement is presented. The
device has an inner and outer housing longitudinally moveable on
one-another which locks in place using a retention member. This can
be locked or fortified by several described options. Also presented
is a method for expanding said device embodiments and a system for
an expandable vertebral body replacement.
Inventors: |
Robinson; James C.;
(Atlanta, GA) ; Pendleton; John E.; (Atlanta,
GA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Robinson; James C.
Pendleton; John E. |
Atlanta
Atlanta |
GA
GA |
US
US |
|
|
Assignee: |
SPECTRUM SPINE IP HOLDINGS,
LLC
Atlanta
GA
|
Family ID: |
51531338 |
Appl. No.: |
14/216893 |
Filed: |
March 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14216513 |
Mar 17, 2014 |
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14216893 |
|
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61802360 |
Mar 15, 2013 |
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Current U.S.
Class: |
623/17.16 |
Current CPC
Class: |
A61F 2002/30235
20130101; A61F 2002/30481 20130101; A61F 2002/3052 20130101; A61F
2002/30593 20130101; A61F 2002/30538 20130101; A61F 2/447 20130101;
A61F 2/4611 20130101; A61F 2002/30494 20130101; A61F 2002/30495
20130101; A61F 2002/30777 20130101; A61F 2002/30523 20130101; A61F
2002/30131 20130101; A61F 2002/30433 20130101; A61F 2002/30471
20130101; A61F 2002/30841 20130101; A61F 2/44 20130101; A61F
2002/30579 20130101; A61F 2002/30601 20130101; A61B 2017/0256
20130101; A61F 2/4455 20130101; A61F 2002/30556 20130101; A61F
2002/2835 20130101; A61F 2002/30904 20130101 |
Class at
Publication: |
623/17.16 |
International
Class: |
A61F 2/44 20060101
A61F002/44 |
Claims
1. A vertebral body replacement device comprising: an outer housing
defining an interior cavity and having an interior toothed surface;
an inner housing nesting within at least a portion of the interior
cavity of the outer housing, the inner housing moveable along a
longitudinal direction to increase a height of the vertebral body
replacement device; a retention member removably engageable with a
portion of the inner housing, the retention member defining at
least one outer edge that is cammed and complimentary to the
interior toothed surface of the outer housing, wherein the
retention member, when positioned in engagement with the inner
housing, permits expansion of the vertebral body replacement device
while preventing contraction of the vertebral body replacement
device; an upper bone contact member having an upper bone contact
surface; and a lower bone contact member having a lower bone
contact surface.
2. The vertebral body replacement device of claim 1, wherein the
inner housing and outer housing define a graft cavity for the
placement of bone graft material.
3. The vertebral body replacement device of claim 1, wherein the
upper bone contact member is pivotally connected to a portion of a
top portion of the outer housing enabling the upper bone contact
member to angulate in either an anterior or posterior
direction.
4. The vertebral body replacement device of claim 1, wherein the
lower bone contact member is pivotally connected to a portion of a
lower portion of the inner housing enabling the lower bone contact
member to angulate in either an anterior or posterior
direction.
5. The vertebral body replacement device of claim 4, wherein at
least one of the upper and lower bone contact members comprise
means for locking the respective upper or lower bone contact member
into a desired angular position.
6. The vertebral body replacement device of claim 5, wherein the
means for locking the respective upper or lower bone contact member
into a desired angular position comprises a wedge member configured
to be removably positioned between the respective bone contact
member and the housing to which the respective bone contact member
is connected.
7. The vertebral body replacement device of claim 1, wherein at
least one of the upper and lower contact surfaces define a
plurality of surface protrusions configured to engage adjacent bony
structure.
8. The vertebral body replacement device of claim 7, wherein the
plurality of surface protrusions are spikes that can move from a
undeployed state, where substantially all of the spike is beneath
the respective contact surface, to a deployed state, where at least
a portion of the spike extends above the respective contact
surface.
9. The vertebral body replacement device of claim 8, further
comprising means for deploying the spikes.
10. A method for replacing a vertebral body comprising the steps
of: accessing a desired motion segment; removing a desired
vertebral body; positioning an expandable VBR device in place of
the removed vertebral body; expanding the expandable VBR device;
and fixing the expandable VBR device in the expanded position; and
wherein the VBR device comprises: an outer housing defining an
interior cavity and having an interior toothed surface; an inner
housing nesting within at least a portion of the interior cavity of
the outer housing, the inner housing moveable along a longitudinal
direction to increase a height of the VBR device; a retention
member removably engageable with a portion of the inner housing,
the retention member defining at least one outer edge that is
cammed and complimentary to the interior toothed surface of the
outer housing, wherein the retention member, when positioned in
engagement with the inner housing, permits expansion of the
vertebral body replacement device while preventing contraction of
the vertebral body replacement device; an upper bone contact member
having an upper bone contact surface; and a lower bone contact
member having a lower bone contact surface.
11. The method of claim 10, wherein the inner housing and outer
housing define a graft cavity for the placement of bone graft
material and the method further comprises the step of packing the
graft cavity with bone growth promoting materials.
12. The method of claim 10, wherein the upper bone contact member
is pivotally connected to a portion of a top portion of the outer
housing enabling the upper bone contact member to angulate in
either an anterior or posterior direction, and the lower bone
contact member is pivotally connected to a portion of a lower
portion of the inner housing enabling the lower bone contact member
to angulate in either an anterior or posterior direction, the
method further comprising the step of fixing a lordotic angle of at
least one of the upper and lower bone contact members.
13. A system for replacing a vertebral body comprising: an
expandable VBR device comprising: an outer housing defining an
interior cavity and having an interior toothed surface; an inner
housing nesting within at least a portion of the interior cavity of
the outer housing, the inner housing moveable along a longitudinal
direction to increase a height of the expandable VBR device; a
retention member removably engageable with a portion of the inner
housing, the retention member defining at least one outer edge that
is cammed and complimentary to the interior toothed surface of the
outer housing, wherein the retention member, when positioned in
engagement with the inner housing, permits expansion of the VBR
device while preventing contraction of the expandable VBR device;
an upper bone contact member having an upper bone contact surface:
and a lower bone contact member having a lower bone contact
surface; and a VBR expansion tool.
14. The system of claim 13, wherein the inner housing and outer
housing define a graft cavity for the placement of bone graft
material.
15. The system of claim 13, wherein the upper bone contact member
is pivotally connected to a portion of a top portion of the outer
housing enabling the upper bone contact member to angulate in
either an anterior or posterior direction and the lower bone
contact member is pivotally connected to a portion of a lower
portion of the inner housing enabling the lower bone contact member
to angulate in either an anterior or posterior direction.
16. The system of claim 15, wherein the VBR expansion tool
comprises: an actuation member having a first handled and an
opposed second handle, wherein the first and second handles are
hingedly coupled at a hinge point, the hinge point being positioned
between a proximal end and a distal end of each of the first and
second handles; and a leveling member coupled to the actuation
member, the leveling member having an upper leveling member and a
lower leveling member, the upper and lower leveling members
separated by and connected by a scissor member, wherein the scissor
member comprises a first scissor arm and a second scissor arm
pinned substantially in their middle section and wherein the
proximal end of the first scissor arm is pinned to a proximal end
of the upper leveling member and the distal end of the first
scissor arm comprises a pin configured to engage, in sliding
relation, an elongate slot defined in the lower leveling member,
and wherein the proximal end of the second scissor arm is pinned to
a proximal end of the lower leveling member and the distal end of
the second scissor arm comprises a pin configured to engage, in
sliding relation, and elongate slot defined in the upper leveling
member such that, as the proximal end of the upper leveling member
is separated from the proximal end of the lower leveling member,
the distal end of the upper leveling member is also raised and
equally separated from the distal end of the lower leveling
member.
17. The system of claim 16, wherein the distal end of the first
handle is hingedly connected to the proximal end of the upper
leveling member and the distal end of the second handle can be
hingedly connected to the proximal end of the lower leveling
member.
18. The system of claim 16, wherein the distal end of the upper and
lower leveling members each comprise forks to engage portions of
the expandable VBR device, whereby, in use, compression of the
handles of the actuation member from a first, separated position to
the second, compressed position, moves the leveling members from a
position substantially adjacent one another to a separated
position.
Description
CONTINUITY
[0001] This application claims priority to and the benefit of U.S.
Provisional Patent Application No. 61/802,360, filed on Mar. 15,
2013 and U.S. Utility application Ser. No. 14/216,513, filed on
Mar. 17, 2014, the contents of which are incorporated herein in
their entirety.
FIELD OF THE INVENTION
[0002] This invention relates generally to spinal surgery, and more
particularly to devices and methods of stabilization of the spine
following removal of a vertebral body, and replacing it with an
expandable construct to stabilize the adjacent bones and provide a
corridor between them for fusion purposes.
BACKGROUND OF THE INVENTION
[0003] Damage to a vertebral bone, often due to a traumatic
fracture or due to invasion of the bone by tumor, at times requires
removal of the vertebral body. This operation is known as a
corpectomy. Following corpectomy, the resultant gap is generally
filled in by a weight bearing support know as a Vertebral Body
Replacement (VBR). This helps to restore and maintain the proper
spacing between the adjacent bones, and often provides an area for
placing graft material to span the adjacent bones in order to allow
a fusion to take place.
[0004] VBRs may be sized to fit the gap, or be expandable over a
range. The expandable VBRs currently available have significant
limitations. These include the inability to adequately pack graft
material in the channel within them post-expansion, a lack of a
satisfactory match of the top and bottom of the implant to the
adjacent bone surfaces, and expansion mechanisms that are complex,
or take an inordinate amount of time to actuate. A need remains for
an implant and surgical technique that will overcome these
shortfalls.
SUMMARY
[0005] Presented herein is an expandable VBR device for use in
spinal surgery following a vertebral corpectomy in the cervical,
thoracic, or lumbar spine. The VBR device comprises an inner
housing and an outer housing. The inner housing and outer housing
can move in relation to one another in the longitudinal direction
to increase or reduce the height of the VBR device. The VBR device
can be expanded within a range from the first, unexpanded position,
to a second fully expanded position or substantially any position
therebetween.
[0006] A system is also presented, the system comprising a VBR
device and a VBR expansion tool. In one exemplified aspect, the VBR
expansion tool comprises an actuation member coupled to a leveling
member. In use, compression of the handles of the actuation member
from the first position to the second position, moves the leveling
members from a position substantially adjacent one another to a
separated position, moving the expandable VBR device from the
unexpanded position to the expanded position.
[0007] A method of placing an expandable VBR into a corpectomy
defect, and expanding the height of the device using a VBR
expansion tool is also presented. The method comprises, accessing
the desired motion segment, removing the desired vertebral body,
positioning the expandable VBR device in place of the removed
vertebral body, expanding the expandable VBR device, and fixing the
expandable VBR device in the expanded position. The method can also
comprise fixing the lordotic angle of the upper and/or lower bone
contact members. In another aspect, the method also comprises
packing the graft cavity with bone growth promoting materials.
[0008] Related methods are also provided. Other apparatuses,
methods, systems, features, and advantages of the expandable VBR
device and the method of its use will be or become apparent to one
with skill in the art upon examination of the following figures and
detailed description. It is intended that all such additional
apparatuses, methods, systems, features, and advantages be included
within this description, be within the scope of the expandable VBR
device and the method of its use, and be protected by the
accompanying claims.
DESCRIPTION OF THE FIGURES
[0009] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate certain aspects
of the instant invention and together with the description, serve
to explain, without limitation, the principles of the invention.
Like reference characters used therein indicate like parts
throughout the several drawings.
[0010] FIG. 1 is a partially exploded front perspective view of one
aspect of a VBR device;
[0011] FIG. 2 is a partially exploded perspective view of the VBR
device of FIG. 1;
[0012] FIG. 3 is a partially exploded side view of the VBR device
of FIG. 1;
[0013] FIG. 4 is a partially exploded front view of the VBR device
of FIG. 1;
[0014] FIG. 5 is a top plan view of the VBR device of FIG. 1;
[0015] FIG. 6 is a front view of another aspect of a VBR device in
the unexpanded position;
[0016] FIG. 7 is a perspective view of the VBR device of FIG. 6 in
an expanded position;
[0017] FIG. 8 is a top plan view of the VBR device of FIG. 6;
[0018] FIG. 9 is a cut away front view of the VBR device of FIG. 6,
showing a ratchet mechanism for restraining the VBR from moving
into the retracted position from the expanded position;
[0019] FIG. 10 is a partial perspective view of an interior wall of
an inner sleeve of the VBR device of FIG. 6, showing the
relationship of a tooth positioned on the interior wall of the
outer sleeve with a recess defined in the exterior wall of the
inner sleeve;
[0020] FIG. 11 is a cutaway view of the engagement of the inner and
outer sleeve of the VBR device of FIG. 10;
[0021] FIG. 12 is a perspective view of the VBR device of FIG. 6,
showing the VBR device positioned between two vertebrae;
[0022] FIG. 13 is a perspective view of the VBR device of FIG. 6,
showing the VBR device with a VBR expansion tool;
[0023] FIG. 14 is a front view of one aspect of a VBR device
showing an inner housing and an outer housing;
[0024] FIG. 15 is a perspective view of the VBR device of FIG.
14;
[0025] FIG. 16 is a cut away front view of the VBR device of FIG.
14, showing gear engaged with a toothed inner surface of the inner
housing;
[0026] FIG. 17 is a top plan view of a retention member; and
[0027] FIG. 18 is a perspective view of the retention member of
FIG. 17;
[0028] FIG. 19 is a front view of one aspect of a VBR device in the
unexpanded position;
[0029] FIG. 20 is a front view of the VBR device of FIG. 19 in the
expanded position, illustrating wedge members angling the bone
contact members;
[0030] FIG. 21 is a front view of the VBR device of FIG. 19 in a
partially expanded position, illustrating wedge members positioned
to keep the bone contact members in a flat position;
[0031] FIG. 22 is a front view of the VBR device of FIG. 21 in the
expanded position;
[0032] FIG. 23 is a perspective view of one aspect of a retention
member for use with a VBR device;
[0033] FIG. 24 is a front elevational view of the retention member
of FIG. 23;
[0034] FIG. 25 is a perspective view of a wedge member for use in a
VBR device;
[0035] FIG. 26 is a perspective view of the VBR device of FIG. 19
in the unexpanded position, illustrating the VBR device between two
vertebrae;
[0036] FIG. 27 is a front view of the VBR device of FIG. 19 in the
expanded position, illustrating the VBR device between two
vertebrae;
[0037] FIG. 28 is a perspective view of the VBR device of FIG. 19
in the expanded position, illustrating the VBR device between two
vertebrae;
[0038] FIG. 29 is a perspective view of the VBR device of FIG. 19
in the expanded position, illustrating the VBR device between two
vertebrae with a retention member in place;
[0039] FIG. 30 is a perspective view of the VBR device of FIG. 19,
showing the VBR device being expanded by an expansion tool;
[0040] FIG. 31 is a perspective view of an outer housing for a VBR
device;
[0041] FIG. 32 is a front view of the outer housing of FIG. 31,
illustrating a blade and slot for locking the angular position of
the bone contact member;
[0042] FIG. 33 as a top view of the outer housing of FIG. 31;
[0043] FIG. 34 is a cut-away front view of the outer housing of
FIG. 31, cut along line 32-32;
[0044] FIG. 35 is a front view of the outer housing of FIG. 31,
illustrating a set screw to lock the blade into position;
[0045] FIG. 36 is a top plan view of the outer housing of FIG.
31;
[0046] FIG. 37 is a front cut-away view of the outer housing of
FIG. 31, cut along line 35-35 of FIG. 33;
[0047] FIG. 38 is a front cut-away view of the outer housing of
FIG. 31, cut along line 38-38 of FIG. 36;
[0048] FIG. 39 is a partially transparent perspective view of an
outer housing for a VBR device having an elongate pivot member to
lock the angular position of the bone contact member;
[0049] FIG. 40 is a front view of the outer housing of FIG. 39;
[0050] FIG. 41 is a partially transparent top plan view of the
outer housing of FIG. 39;
[0051] FIG. 42 is a cut-away side view of the outer housing of FIG.
39, cut along line 42-42 of FIG. 40;
[0052] FIG. 43 is a front view of the outer housing of FIG. 39,
illustrating the upper bone contact member in the angled
position;
[0053] FIG. 44 is a partially transparent top plan view of the
outer housing of FIG. 39, showing a trough for receipt of a pivot
member;
[0054] FIG. 45 is a cut-away side view of the outer housing of FIG.
39, cut along line 45-45 of FIG. 43;
[0055] FIG. 46 is a cut-away front view of the outer housing of
FIG. 39, cut along line 46-46 of FIG. 44;
[0056] FIG. 47 is a perspective view of the outer housing of FIG.
39, illustrating the trough and engagement portion of the
trough;
[0057] FIG. 48 is a section view of a section of the outer housing
of FIG. 39 showing the section of FIG. 47;
[0058] FIG. 49 is a partially transparent perspective view of a VBR
device, illustrating deployable spikes corresponding to an upper
bone contact member;
[0059] FIG. 50 is a partially transparent cut-away perspective view
of the VBR device of FIG. 49, illustrating ramp members associated
with deployable spikes;
[0060] FIG. 50A is a perspective view of a ramp member and
deployable spikes for use in the VBR device of FIG. 49;
[0061] FIG. 51 is a side view of the VBR device of FIG. 49,
illustrating the spikes in a retracted position;
[0062] FIG. 52 is a cut-away front view of the VBR device of FIG.
49, cut along line 52-52 of FIG. 51;
[0063] FIG. 53 is a rear view of the VBR device of FIG. 49,
illustrating the spikes in a retracted position;
[0064] FIG. 54 is a cut-away side view of the VBR device of FIG.
49, cut along line 54-54 of FIG. 53;
[0065] FIG. 55 is a side view of the VBR device of FIG. 49,
illustrating the spikes in a deployed position;
[0066] FIG. 56 is a cut-away front view of the VBR device of FIG.
49, cut along line 56-56 of FIG. 55;
[0067] FIG. 57 is a rear view of the VBR device of FIG. 49,
illustrating the spikes in a deployed position;
[0068] FIG. 58 is cut-away side view of the VBR device of FIG. 49,
cut along line 58-58 of FIG. 57;
[0069] FIG. 59 is a partially transparent perspective view of a VBR
device illustrating deployable flexible spikes;
[0070] FIG. 60 is a partially transparent side view of the VBR
device of FIG. 59, illustrating the spikes in a retracted
position;
[0071] FIG. 61 is a cut-away top plan view of the VBR device of
FIG. 59, cut along line 61-61 of FIG. 60;
[0072] FIG. 62 is a rear view of the VBR device of FIG. 59,
illustrating the spikes in a retracted position;
[0073] FIG. 63 is a cut-away side view of the VBR device of FIG.
59, cut along line 63-63 of FIG. 62;
[0074] FIG. 64 is a partially transparent side view of the VBR
device of FIG. 59, illustrating the spikes in a deployed
position;
[0075] FIG. 65 is a cut-away top plan view of the VBR device of
FIG. 59, cut along line 65-65 of FIG. 64;
[0076] FIG. 66 is a rear view of the VBR device of FIG. 59,
illustrating the spikes in a deployed position;
[0077] FIG. 67 is a cut-away side view of the VBR device of FIG.
59, cut along line 67-67 of FIG. 66;
[0078] FIG. 68 is a perspective view of one aspect of a VBR device
and a VBR device expansion tool;
[0079] FIG. 69 is a side view of the VBR expansion tool of FIG. 68,
illustrating the VBR expansion tool engaged with the VBR device in
the retracted or unexpanded position;
[0080] FIG. 70 is a side view of the VBR expansion tool of FIG. 68,
illustrating the VBR expansion tool engaged with the VBR device
after expansion; and
[0081] FIG. 71 is a side view of a scissor member for a VBR
expansion tool.
DESCRIPTION OF THE INVENTION
[0082] The present invention can be understood more readily by
reference to the following detailed description, examples, and
claims, and their previous and following description. Before the
present system, devices, and/or methods are disclosed and
described, it is to be understood that this invention is not
limited to the specific systems, devices, and/or methods disclosed
unless otherwise specified, as such can, of course, vary. It is
also to be understood that the terminology used herein is for the
purpose of describing particular aspects only and is not intended
to be limiting.
[0083] The following description of the invention is provided as an
enabling teaching of the invention in its best, currently known
aspect. Those skilled in the relevant art will recognize that many
changes can be made to the aspects described, while still obtaining
the beneficial results of the present invention. It will also be
apparent that some of the desired benefits of the present invention
can be obtained by selecting some of the features of the present
invention without utilizing other features. Accordingly, those who
work in the art will recognize that many modifications and
adaptations to the present invention are possible and can even be
desirable in certain circumstances and are a part of the present
invention. Thus, the following description is provided as
illustrative of the principles of the present invention and not in
limitation thereof.
[0084] As used herein, the singular forms "a," "an" and "the"
include plural referents unless the context clearly dictates
otherwise. Thus, for example, reference to a "plate" includes
aspects having two or more plates unless the context clearly
indicates otherwise.
[0085] Ranges can be expressed herein as from "about" one
particular value, and/or to "about" another particular value. When
such a range is expressed, another aspect includes from the one
particular value and/or to the other particular value. Similarly,
when values are expressed as approximations, by use of the
antecedent "about," it will be understood that the particular value
forms another aspect. It will be further understood that the
endpoints of each of the ranges are significant both in relation to
the other endpoint, and independently of the other endpoint.
[0086] As used herein, the terms "optional" or "optionally" mean
that the subsequently described event or circumstance may or may
not occur, and that the description includes instances where said
event or circumstance occurs and instances where it does not.
[0087] Terms used herein, such as "exemplary" or "exemplified," are
not meant to show preference, but rather to explain that the aspect
discussed thereafter is merely one example of the aspect
presented.
[0088] Additionally, as used herein, relative terms, such as
"substantially", "generally", "approximately", and the like, are
utilized herein to represent an inherent degree of uncertainty that
may be attributed to any quantitative comparison, value,
measurement, or other representation. These terms are also utilized
herein to represent the degree by which a quantitative
representation may vary from a stated reference without resulting
in a change in the basic function of the subject matter at
issue.
[0089] In one aspect, presented herein is an expandable VBR device
10 for use in spinal surgery following a vertebral corpectomy in
the cervical, thoracic, or lumbar spine. The VBR device comprises
an inner housing 100 and an outer housing 200. The inner housing
100 and outer housing 200 can move in relation to one another in
the longitudinal direction to increase or reduce the height of the
VBR device 10. In one exemplified aspect, the outer housing defines
in interior cavity 210 within which the inner housing can nest in
the unexpanded position. In another aspect, the inner housing 100
and outer housing 200, together, define a graft cavity 215 for the
placement of bone graft material, to include, but not limited to,
allograft, bone substitute, or other biocompatible bone growth
promoting materials.
[0090] The VBR device can be expanded within a range from the
first, unexpanded position, to a second fully expanded position or
substantially any position therebetween. In an exemplified aspect,
an interior surface 220 of the outer housing 200 comprises a
toothed surface 225. A toothed surface can be positive, such as
protrusions, or negative, such as recesses. In one aspect, the
exterior surface 110 of the inner housing 100 comprises a toothed
surface 125, as well. Each tooth can comprise a cam 130, 230
surface and a flat surface 135, 235. In one aspect, the toothed
surfaces are complimentarily opposite, meaning that in the
expanding direction, the cam surface 230 of a tooth 225 on the
outer housing 200 mates with the cam surface 130 of a tooth 125 on
the inner housing 100 and, in the retracting direction, the flat
surface 235 of a tooth 230 on the outer housing 200 engages the
flat surface 135 of a tooth 125 on the inner housing 100. This
relationship permits the two housings to move in the expanding
direction in a ratcheting manner, but prevents the two housings to
move in the retracting direction.
[0091] In another exemplified aspect, each tooth 125, 225 can
comprise two cam surfaces 130, 230, without a flat surface.
Additionally, the VBR device can comprise a retention member 300
configured to engage at least a portion of the toothed surface of
the inner housing to prevent longitudinal up and down movement of
the outer housing with respect to the inner housing. In one aspect,
the retention member can be a u-shaped member sized to horizontally
slide around at least at least portions the exterior surface 110 of
the inner housing 100.
[0092] In still another exemplified aspect, the inner housing may
define a window 160 having a toothed edge portion 165. In this
aspect, a gear 260 can be positioned on the outer housing 200
configured to engage the toothed edge portion 165 of the window 160
of the inner housing 100. In one aspect, the exterior surface 110
of the inner housing may comprise a toothed surface 125. The VBR
device can also comprise a retention member 300 configured to
engage the exterior surface of the inner housing to restrict
movement of the inner housing with respect to the outer housing.
The retention member can be a c-ring configured to at least
partially wrap around the inner housing and engage at least one of
the teeth on the external surface of the inner housing.
[0093] The retention member 300 can have, for example, edge portion
310 that are cammed and complimentary to the toothed surfaces 225
of the interior surface 220 of the outer housing 200. However,
since the toothed surfaces are generally sloped, the edge portion
of the retention member need not be angled, sloped, or cammed. It
is also contemplated that the edge portion 310 of the retention
member have a top surface 315 that is substantially flat in order
to retain the flat portion 235 of the toothed surfaces 225 of the
interior surface 220 of the outer housing 200. In still another
aspect, the retention member can be removably attached to a portion
of the inner housing. As illustrated in FIG. 20, the top portion
140 of the inner housing 100 can comprise a tongue 145 and the edge
portion 310 of the retention member 300 can comprise a
corresponding groove 320 to enable the retention member to slide
into position at a top portion of the inner housing. In this
aspect, when the retention member is positioned in engagement with
the inner housing, the outer housing is prevented from retracting
downward toward the unexpanded position, while still being able to
ratchet in the upward direction toward the expanded position. When
the retention member is moved out of engagement with the inner
housing, the outer housing can therefore move in either direction
substantially unimpeded.
[0094] In an exemplified aspect, the VBR device comprises an upper
bone contact member 400 and a lower bone contact member 450. The
upper bone contact member 400 has an upper bone contact surface 410
configured for contact with a lower portion of a first vertebra.
The lower bone contact member 450 has a lower bone contact surface
460 configured for contact with an upper portion of a second
vertebra. One or both of the upper and lower bone contact members
can be substantially planar. In one aspect, the upper bone contact
member can be pivotally connected to a portion of the top portion
240 of the outer housing. The pivot point 415 can, for example, be
in substantially the center of the of the upper bone contact
member, enable the upper bone contact member to angulate in either
the anterior or posterior direction. The function permits the VBR
device to adapt to the anatomy of the patient. As can be
appreciated, the lower bone contact member 450 can be pivotally
connected to a portion of the bottom portion 150 of the inner
housing 100. The pivot point 465 can, for example, be in
substantially the center of the of the lower bone contact member
450, enabling the lower bone contact member to angulate in either
the anterior or posterior direction.
[0095] In still another aspect, the VBR device comprises an inner
and outer sleeve 500, 550, wherein the outer and inner sleeves are
configured to move longitudinally with respect to one another from
the retracted position to the expanded position. The inner and
outer sleeve define an interior cavity 555. In an exemplified
aspect, an interior surface 560 of the outer sleeve 550 comprises a
toothed surface 565. In one aspect, the exterior surface 510 of the
inner sleeve 500 comprises a toothed surface 515, as well. Each
tooth can comprise a cam surface 516, 566 and a flat surface 517,
567. In one aspect, the toothed surfaces are complimentarily
opposite, meaning that in the expanding direction, the cam surface
of a tooth on the outer sleeve mates with the cam surface of a
tooth on the inner sleeve and, in the retracting direction, the
flat surface of a tooth on the outer sleeve engages the flat
surface of a tooth on the inner sleeve This relationship permits
the two sleeves to move in the expanding direction in a ratcheting
manner, but prevents the two sleeves to move in the retracting
direction. As one skilled in the art can appreciate, in lieu of
complimentary toothed surfaces, the inner and outer sleeves can
comprise one toothed surface and define a complimentary recess 520
on the other surface, where the recess 520 has a flat interior edge
522 that compliments the flat surface 567 of the tooth of the other
surface.
[0096] In this aspect, the upper bone contact member can be
hingedly attached to a top portion 580 of the outer sleeve and the
lower bone contact member can be hingedly attached to a lower
portion 530 of the inner sleeve. This configuration permits
angulation of the bone contact members to compliment the adjacent
vertebral bodies. In an exemplified aspect, the inner and outer
sleeves nest within one another and define a pillar window 570. In
this aspect, the VBR device comprise a pillar 20 configured to fit
within the interior cavity 555 to be placed into the interior
cavity via the pillar window 570. In an exemplified aspect, a top
portion 21 of the pillar is angled and the bottom portion of the
pillar 22 is also angled. The top portion 21 of the pillar engages
a portion of the upper bone contact member 400 and the angle of the
top portion of the pillar places the upper bone contact member to
the desired angle for lordosis. Similarly, the bottom portion 22 of
the pillar engages a portion of the lower bone contact member 450
and the angle of the lower portion of pillar places the lower bone
contact member to the desired angle for lordosis. The pillar, of
course, substantially prevents the VBR device from moving from the
expanded position to the retracted position.
[0097] One or both of the upper and lower bone contact members 400,
450 can comprise spikes 600 or protrusions to facilitate engagement
with the respective vertebral bone. The spikes can be integral with
the respective upper or lower bone contact member or they can be
deployed after insertion into the disc space. In one exemplified
aspect, as illustrated in FIG. 42, the respective bone contact
member can define at least one spike aperture 610 in communication
with a spike cavity 620. A spike can be sized to fit substantially
completely therein the spike cavity 620. In one aspect, a ramp
member 630 can be positioned within a channel 650 defined in the
bone contact member defining an orifice 635 that is partially
coaxial with the spike cavity 620. The edges of the orifice and the
spike comprise complimentary cam 640 and follower 645 surfaces such
that, when the ramp member 630 is moved in a first direction, the
spike rides along the ramp member, raising it to extend the distal
portion of the spike above the bone contact surface of the bone
contact member. Of course, it is contemplated that the spike can
comprise a plurality of spikes and the spike cavity can comprise a
plurality of spike cavities. Additionally, the ramp member can
comprise a plurality of ramp members. Each ramp member may define a
plurality of orifices, each corresponding to a spike and spike
cavity, as illustrated in FIG. 42.
[0098] In another aspect, the spikes 600 can comprise a flexible
material, such as Nitinol or spring steel. In this aspect, the
spikes can be initially embedded within a channel 650 in the
respective bone contact member in a plane that is substantially
parallel to the respective bone contact surface. Each of the spike
apertures 610 can be associated with a ramped or angled portion 655
of the bone contact member such that, when the flexible spike is
moved toward the spike aperture, the spike will angle upward and
through the spike aperture.
[0099] In one exemplified aspect, one or both of the bone contact
members can be locked in angular position, substantially
restraining the respective bone contact member from pivoting with
respect to the respective inner or outer housing. In one aspect, as
shown in FIG. 25, the respective bone contact member can comprise a
blade 700 positioned on a second surface 420, 470 of the bone
contact member 400, 450, opposite the bone contact surface, and
substantially perpendicular thereto the second surface. In this
aspect, the top of the outer housing, or the bottom of the inner
housing, depending on which bone contact member is being discussed,
can define a blade slot 710 configured for receipt of the blade
700. The respective housing can also define a threaded aperture 720
configured for receipt of a set screw 730 adapted to fit within the
threaded aperture 720 and engage a portion of the blade 700 to
substantially fix its position with respect to the respective
housing. As shown in the figures, the blade can define a plurality
of blade apertures into which the end of the set screw can engage
to assist in holding the respective bone contact member in angular
position.
[0100] In another aspect, as shown in FIG. 32a, the respective bone
contact member can comprise at least one elongate pivot member 800
configured to fit within a respective trough 810 defined in the top
surface 240 of the outer housing (or the bottom surface of the
inner housing). The elongate pivot member 800 can comprise a
substantially cylindrical shape, but other shapes are contemplated.
In one aspect at least a distal end 805 of the elongate pivot
member can define a raised and/or depressed pattern 820. In this
aspect, a portion of the trough 810 defines a complimentarily
patterned raised and/or depressed section 825. In one aspect, the
pattern is a starburst, as shown in FIG. 32a, but other
complimentary patterns are contemplated. In this aspect, urging the
distal end of the pivot member into engagement with the patterned
portion of the trough fixes the angle of the bone contact member
with respect to the respective housing. For example, a set screw
830 may be used, as shown in FIG. 37, to urge the pivot member into
engagement with the patterned portion of the trough.
[0101] In still another aspect, the respective bone contact member
can be locking into angular position by insertion of a wedge member
900 in the space between the bone contact member and the respective
housing. FIG. 20 shows a wedge member between the upper bone
contact member and the outer housing and another wedge member
between the lower bone contact member and the inner housing. The
wedge members can be configured in various ways to achieve the
desired angle. In one aspect, the wedge member can be fixed to the
VBR with a fixation device, such as a screw.
[0102] A system is presented, comprising a VBR device and a VBR
expansion tool 1000. In one exemplified aspect, the VBR expansion
tool 1000 comprises an actuation member 1100 coupled to a leveling
member 1200. The actuation member comprises a first handle 1110
hingedly coupled to an opposed second handle 1120. The first handle
comprises a proximal end 1112 configured to be held by a person's
hand and a distal end 1114, with a hinge point 1130 therebetween.
The second handle 1120 also comprises a proximal end 1122
configured to be held by a person's hand and a distal end 1124,
with the hinge point therebetween 1130. The actuation member is
configured to move from a first position where the proximal ends of
the handles are at their most separated position and where the
distal ends of the handles are at substantially their closest
position, to a second position where the proximal ends of the
handles are compressed toward one another and where the distal ends
of the handles are separated. The VBR expansion tool can also
comprise a compression retention member 1140 hingedly connected to
a proximal end of one of the first or second handles configured to
engage a catch mechanism 1145 positioned on the other handle. The
compression retention member, when engaged with the catch
mechanism, substantially maintains pressure on the first and second
handles.
[0103] Continuing with the VBR expansion tool, the leveling member
1200 comprises an upper leveling member 1210 and a lower leveling
member 1220, the two leveling members are separated by and
connected by a scissor member 1250. The scissor member comprises a
first scissor arm 1260 and a second scissor arm 1270. The scissor
arms 1260, 1270 are pinned substantially in their middle section
1280, similar to common scissors. The proximal end 1262 of the
first scissor arm 1260 is pinned to a proximal end 1212 of the
upper leveling member 1210 and the distal end 1264 of the first
scissor arm comprises a first pin 1266 configured to engage, in
sliding relation, an elongate slot 1218 defined in the lower
leveling member. Similarly, the proximal end 1272 of the second
scissor arm 1270 is pinned to a proximal end 1222 of the lower
leveling member 1220 and the distal end 1274 of the second scissor
arm comprises a second pin 1276 configured to engage, in sliding
relation, and elongate slot 1216 defined in the upper leveling
member. In this fashion, as the proximal end of the upper leveling
member is separated from the proximal end of the lower leveling
member, the distal end of the upper leveling member is also raised
and equally separated from the distal end of the lower leveling
member. As can be appreciated, the relation of the arms to the
leveling members can be reversed with similar results.
[0104] As illustrated in FIG. 69, the distal end of the first
handle 1114 can be hingedly connected to the proximal end 1214 of
the upper leveling member and the distal end 1124 of the second
handle can be hingedly connected to the proximal end 1222 of the
lower leveling member. Additionally the distal end of the upper and
lower leveling members can comprise forks 1300 to engage portions
of the expandable VBR device. In use, compression of the handles of
the actuation member from the first position to the second
position, moves the leveling members from a position substantially
adjacent one another to a separated position. By doing so, when the
forks are engaged with portions of the inner and outer housings,
the expandable VBR device moves from the unexpanded position to the
expanded position.
[0105] A method of placing an expandable VBR into a corpectomy
defect, and expanding the height of the device using a VBR
expansion tool is presented. The method comprises, accessing the
desired motion segment, removing the desired vertebral body,
positioning the expandable VBR device in place of the removed
vertebral body, expanding the expandable VBR device, and fixing the
expandable VBR device in the expanded position. The method can also
comprise fixing the lordotic angle of the upper and/or lower bone
contact members. In another aspect, the method also comprises
packing the graft cavity with bone growth promoting materials.
[0106] Although several aspects of the invention have been
disclosed in the foregoing specification, it is understood by those
skilled in the art that many modifications and other aspects of the
invention will come to mind to which the invention pertains, having
the benefit of the teaching presented in the foregoing description
and associated drawings. It is thus understood that the invention
is not limited to the specific aspects disclosed hereinabove, and
that many modifications and other aspects are intended to be
included within the scope of the appended claims. Moreover,
although specific terms are employed herein, as well as in the
claims that follow, they are used only in a generic and descriptive
sense, and not for the purposes of limiting the described
invention.
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