U.S. patent application number 12/124632 was filed with the patent office on 2009-05-21 for delivery system and method for inflatable devices.
Invention is credited to Mark Goldin, Brian Schumacher.
Application Number | 20090131952 12/124632 |
Document ID | / |
Family ID | 39884742 |
Filed Date | 2009-05-21 |
United States Patent
Application |
20090131952 |
Kind Code |
A1 |
Schumacher; Brian ; et
al. |
May 21, 2009 |
DELIVERY SYSTEM AND METHOD FOR INFLATABLE DEVICES
Abstract
Provided is a flowable material delivery system and method
comprising one or a plurality of tentacles associated with an
inflatable member. The tentacles are configured to deliver bone
cement to a vertebral cavity upon reduction of a vertebral
compression fracture. The tentacles may be coupled with the outer
surface of an inflatable member or pass through the inflatable
member to deliver a flowable material to a tissue cavity.
Inventors: |
Schumacher; Brian; (Orlando,
FL) ; Goldin; Mark; (Orlando, FL) |
Correspondence
Address: |
FROST BROWN TODD, LLC
2200 PNC CENTER, 201 E. FIFTH STREET
CINCINNATI
OH
45202
US
|
Family ID: |
39884742 |
Appl. No.: |
12/124632 |
Filed: |
May 21, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60939355 |
May 21, 2007 |
|
|
|
60939365 |
May 21, 2007 |
|
|
|
60939362 |
May 21, 2007 |
|
|
|
Current U.S.
Class: |
606/105 ;
606/108; 606/192 |
Current CPC
Class: |
A61B 2017/2927 20130101;
A61B 17/1671 20130101; A61B 17/8816 20130101; A61B 17/320016
20130101; A61B 17/8855 20130101; A61B 17/1617 20130101; A61B
2017/00557 20130101; A61B 17/8805 20130101; A61B 17/3472
20130101 |
Class at
Publication: |
606/105 ;
606/192; 606/108 |
International
Class: |
A61B 17/58 20060101
A61B017/58; A61F 11/00 20060101 A61F011/00; A61M 29/00 20060101
A61M029/00 |
Claims
1. An orthopedic fracture reduction apparatus comprising: (a) an
inflatable member, the inflatable member having an inner surface
and an outer surface; (b) an inflation lumen, the inflation lumen
being in fluid communication with the inflatable member, wherein
the inflation lumen is configured for the delivery of flowable
material to inflate and deflate the inflatable member; (c) a
tentacle, the tentacle being associated with the inflation member,
wherein the tentacle includes at least one aperture; and (d) a
delivery lumen, the delivery lumen being in fluid communication
with the tentacle, wherein the delivery lumen is configured for the
delivery of flowable material into the tentacle and through the at
least one aperture.
2. The apparatus of claim 1, wherein the at least one aperture
comprises a plurality of apertures.
3. The apparatus of claim 1, wherein the tentacle is coupled with
the outer surface of the inflatable member.
4. The apparatus of claim 1, wherein the tentacle is configured to
deliver bone cement through the at least one aperture into a
vertebral cavity.
5. The apparatus of claim 1, wherein the tentacle and the delivery
lumen comprise a contiguous lumen.
6. The apparatus of claim 1, further comprising a plurality of
tentacles, wherein each of the plurality of tentacles comprises at
least one aperture.
7. The apparatus of claim 6, wherein the at least one aperture
comprises a plurality of apertures.
8. The apparatus of claim 6, wherein the plurality of tentacles are
associated with the inflation lumen, wherein the inflation lumen is
configured to deliver flowable material to each of the plurality of
tentacles.
9. The apparatus of claim 6, wherein each of the plurality of
tentacles is associated with the outer surface of the inflatable
member.
10. The apparatus of claim 6, wherein the plurality of tentacles
are associated with a plurality of delivery lumens.
11. The apparatus of claim 10, wherein each of the plurality of
tentacles is associated with one of the plurality of delivery
lumens.
12. The apparatus of claim 1, wherein the tentacle passes through
the inflatable member.
13. The apparatus of claim 1, wherein the delivery lumen is a rigid
tube and the tentacle is a flexible member.
14. The apparatus of claim 1, wherein the delivery lumen and the
tentacle are a contiguous flexible lumen.
15. The apparatus of claim 1, wherein the tentacle is integral with
the outer surface of the inflatable member.
16. The apparatus of claim 1, wherein the at least one aperture is
targeted to deliver the flowable material to a predetermined
region.
17. The apparatus of claim 16, where the predetermined region is
the posterior side of a vertebral body.
18. The apparatus of claim 1, wherein the tentacle substantially
sheaths the inflatable member.
19. An orthopedic fracture reduction apparatus comprising: (a) an
inflatable member, the inflatable member having an inner surface
and an outer surface; (b) an inflation lumen, the inflation lumen
being in fluid communication with the inflatable member, wherein
the inflation lumen is configured for the delivery of flowable
material to inflate and deflate the inflatable member; (c) a
delivery lumen, wherein the flowable material delivery lumen passes
through the inflatable member, wherein the flowable material
delivery lumen is configured to deliver flowable material through
the inflatable member; (d) a tentacle, the tentacle being
associated with the inflation member, wherein the tentacle includes
at least one aperture; and (e) a tentacle delivery lumen, the
tentacle delivery lumen being in fluid communication with the
tentacle, wherein the tentacle delivery lumen is configured for the
delivery of flowable material into the tentacle and through the at
least one aperture.
20. The apparatus of claim 19, wherein the at least one aperture
comprises a plurality of apertures.
21. The apparatus of claim 19, wherein the tentacle is coupled with
the outer surface of the inflatable member.
22. The apparatus of claim 19, further comprising a plurality of
tentacles, wherein each of the plurality of tentacles comprises at
least one aperture.
23. A method for providing a therapeutic effect comprising the
steps of: providing a tissue manipulation apparatus, the tissue
manipulation apparatus comprising; (a) an inflatable member, the
inflatable member having an inner surface and an outer surface; (b)
an inflation lumen, the inflation lumen being in fluid
communication with the inflatable member, wherein the inflation
lumen is configured for the delivery of flowable material to
inflate and deflate the inflatable member; (c) a tentacle, the
tentacle being associated with the inflation member, wherein the
tentacle includes at least one aperture; and (d) a tentacle
delivery lumen, the tentacle delivery lumen being in fluid
communication with the tentacle, wherein the tentacle delivery
lumen is configured for the delivery of flowable material into the
tentacle and through the at least one aperture; inserting the
tissue manipulation apparatus into tissue; inflating the inflatable
member via the inflation lumen; and delivering flowable material
through the tentacle via the tentacle delivery lumen.
24. The method of claim 23, further comprising the step of
deflating the inflatable member gradually while delivering flowable
material through the tentacle.
25. The method of claim 23, wherein the fracture reduction device
further comprises a first tentacle that passes through the
inflatable member and a second tentacle associated with the outer
surface of the inflatable member.
26. The method of claim 25, further comprising the step of
delivering flowable material through the first tentacle and the
second tentacle simultaneously.
27. The method of claim 25, further comprising the steps of,
gradually deflating the inflatable member; and delivering flowable
material through the first tentacle as the inflatable member is
27.
28. The method of claim 25, further comprising the steps of,
gradually deflating the inflatable member; and delivering flowable
material through the second tentacle as the inflatable member is
gradually deflated.
29. The method of claim 25, further comprising the step of
delivering flowable material through the first tentacle and the
second tentacle while the inflatable member is inflated.
30. The method of claim 23, wherein the tentacle is associated with
the outer surface of the inflation member.
31. The method of claim 23, wherein the tentacle passes through the
center of the inflatable member.
32. The method of claim 23, wherein the tissue is orthopedic
tissue.
33. The method of claim 32, wherein the orthopedic tissue is spinal
tissue.
34. The method of claim 33, wherein the spinal tissue is vertebral
tissue.
35. The method of claim 34, wherein the inflatable member is used
to reduce a fracture in the vertebral tissue.
36. The method of claim 23, further comprising the step of
delivering flowable material through the tentacle via the tentacle
delivery lumen prior to inflating the inflatable member.
Description
PRIORITY
[0001] The application claims priority from the disclosures of U.S.
Provisional Patent Application Ser. No. 60/939,355, entitled
"Articulating Cavitation Device," filed May 21, 2007, U.S.
Provisional Patent Application Ser. No. 60/939,365, entitled
"Extendable Cutting Member," filed May 21, 2007, and U.S.
Provisional Patent Application Ser. No. 60/939,362, entitled
"Delivery System and Method for Inflatable Devices," filed May 21,
2007, which are herein incorporated by reference in their
entirety.
BACKGROUND
[0002] Versions of the present invention relate to restoring the
anatomy of fractured bone and, more particularly, to restoring the
anatomy of fractured bone with an inflatable device.
[0003] Increasingly, surgeons are using minimally invasive surgical
techniques for the treatment of a wide variety of medical
conditions. Such techniques typically involve the insertion of a
surgical device through a natural body orifice or through a
relatively small incision using a tube or cannula. In contrast,
conventional surgical techniques typically involve a significantly
larger incision and are, therefore, sometimes referred to as open
surgery. Thus, as compared with conventional techniques, minimally
invasive surgical techniques offer the advantages of minimizing
trauma to healthy tissue, minimizing blood loss, reducing the risk
of complications such as infection, and reducing recovery time.
Further, certain minimally invasive surgical techniques may be
performed under local anesthesia or even, in some cases, without
anesthesia, and therefore enable surgeons to treat patients who
would not tolerate the general anesthesia required by conventional
techniques.
[0004] Surgical procedures often require the formation of a cavity
within either soft or hard tissue, including bone. Tissue cavities
are formed for a wide variety of reasons, such as for the removal
of diseased tissue, for harvesting tissue in connection with a
biopsy or autogenous transplant, and for implant fixation. To
achieve the benefits associated with minimally invasive techniques,
tissue cavities are generally formed by creating only a relatively
small access opening in the target tissue. An instrument or device
may then be inserted through the opening and used to form a hollow
cavity that is significantly larger than the access opening.
[0005] One surgical application utilizing the formation of a cavity
within tissue is the surgical treatment and prevention of skeletal
fractures associated with osteoporosis, which is a metabolic
disease characterized by a decrease in bone mass and strength. The
disease frequently leads to skeletal fractures under light to
moderate trauma and, in its advanced state, can lead to fractures
under normal physiologic loading conditions. It is estimated that
osteoporosis affects approximately 15-20 million people in the
United States and that approximately 1.3 million new fractures each
year are associated with osteoporosis, with the most common
fracture sites being the hip, wrist, and vertebrae.
[0006] An emerging prophylactic treatment for osteoporosis, trauma,
or the like involves replacing weakened bone with a stronger
synthetic bone substitute using minimally invasive surgical
procedures. The weakened bone is first surgically removed from the
affected site, thereby forming a cavity. The cavity is then filled
with an injectable synthetic bone substitute and allowed to harden.
The synthetic bone substitute provides structural reinforcement and
thus lessens the risk of fracture of the affected bone. Without the
availability of minimally invasive surgical procedures the
prophylactic fixation of osteoporosis-weakened bone in this manner
would not be practical because of the increased morbidity, blood
loss, and risk of complications associated with conventional
procedures. Moreover, minimally invasive techniques tend to
preserve more of the remaining structural integrity of the bone
because they minimize surgical trauma to healthy tissue.
[0007] Other less common conditions in which structural
reinforcement of bone may be appropriate include bone cancer and
avascular necrosis. Surgical treatment for each of these conditions
can involve removal of the diseased tissue by creating a tissue
cavity and filling the cavity with a stronger synthetic bone
substitute to provide structural reinforcement to the affected
bone.
[0008] Medical balloons are commonly known for dilating and
unblocking arteries that feed the heart (percutaneous translumenal
coronary angioplasty) and for arteries other than the coronary
arteries (noncoronary percutaneous translumenal angioplasty). In
angioplasty, the balloon is tightly wrapped around a catheter shaft
to minimize its profile, and is inserted through the skin and into
the narrowed section of the artery. The balloon is inflated,
typically, by saline or a radiopaque solution, which is forced into
the balloon through a syringe. Conversely, for retraction, a vacuum
is pulled through the balloon to collapse it.
[0009] Medical balloons also have been used for the treatment of
bone fractures. One such device is disclosed in U.S. Pat. No.
5,423,850 to Berger, which teaches a method and an assembly for
setting a fractured tubular bone using a balloon catheter. The
balloon is inserted far away from the fracture site through an
incision in the bone, and guide wires are used to transport the
uninflated balloon through the medullary canal and past the
fracture site for deployment. The inflated balloon is held securely
in place by the positive pressure applied to the intramedullary
walls of the bone. Once the balloon is deployed, the attached
catheter tube is tensioned with a calibrated force measuring
device. The tightening of the catheter with the fixed balloon in
place aligns the fracture and compresses the proximal and distal
portions of the fractured bone together. The tensioned catheter is
then secured to the bone at the insertion site with a screw or
similar fixating device.
BRIEF DESCRIPTION OF THE FIGURES
[0010] It is believed that versions of the present invention will
be better understood from the following description taken in
conjunction with the accompanying drawings. The drawings and
detailed description that follow are intended to be merely
illustrative and are not intended to limit the scope of the
invention.
[0011] FIG. 1 depicts a perspective side view of one version of a
trocar and cannula assembly of a vertebral cavity formation and
fracture reduction system.
[0012] FIG. 2 depicts a perspective side view of the trocar of FIG.
1 shown after removal from the cannula of the assembly.
[0013] FIG. 3 depicts a perspective side view of the cannula of
FIG. 1 shown after removal of the trocar from the assembly.
[0014] FIG. 4 depicts a perspective side view of one version of a
drill that is configured for insertion through the cannula of FIG.
3.
[0015] FIG. 5 depicts a perspective view of one version of a cavity
formation instrument of a vertebral cavity formation and fracture
reduction system shown in the articulated position.
[0016] FIG. 6 depicts a longitudinal, cross-section view of the
cavity formation instrument of FIG. 5 shown in the unarticulated
position.
[0017] FIG. 7 depicts a more detailed view of the longitudinal,
cross-section view of FIG. 6 showing the handle portion of the
cavity formation instrument.
[0018] FIG. 8 depicts a more detailed view of the longitudinal,
cross-section view of FIG. 6 showing the end effector portion of
the cavity formation instrument in the unarticulated position.
[0019] FIG. 9 depicts a more detailed view of the longitudinal,
cross-section view of FIG. 6 showing the end effector portion of
the cavity formation instrument in the articulated position.
[0020] FIG. 10 depicts a perspective side view of one version of a
vertebral fracture reduction apparatus of a vertebral cavity
formation and fracture reduction system.
[0021] FIG. 11 depicts a longitudinal, cross-section view of the
vertebral fracture reduction apparatus of FIG. 10.
[0022] FIG. 12 depicts a more detailed perspective side view of the
access ports and port housing of the vertebral fracture reduction
apparatus of FIG. 10.
[0023] FIG. 13 depicts a more detailed perspective side view of the
balloon and delivery tentacle of the vertebral fracture reduction
apparatus of FIG. 10.
[0024] FIG. 14 depicts a transverse, cross-section view of the
balloon, delivery lumens, and insertion sheath of the vertebral
fracture reduction apparatus of FIG. 10.
[0025] FIG. 15 depicts a flowchart of one version of a vertebral
cavity formation and fracture reduction method.
[0026] FIG. 16 depicts a longitudinal, cross-section view of a
medical device having an extendable cutting member coupled with a
transition member shown in an extended position.
[0027] FIG. 17 depicts a longitudinal, cross-section view of the
extendable cutting member of FIG. 16 shown in a retracted
position.
[0028] FIG. 18 depicts a transverse, cross-section view of the
medical device of FIG. 16 taken along reference line 3-3 showing
the transition member.
[0029] FIG. 19 depicts a longitudinal, cross-section view of an
alternate version of a medical device having an extendable cutting
member coupled with a shaft member shown in an extended
position.
[0030] FIG. 20 depicts a longitudinal, cross-section view of the
extendable cutting member of FIG. 19 shown in a retracted
position.
[0031] FIG. 21 depicts a transverse, cross-section view of a
medical device taken along reference 3-3 of FIG. 16 illustrating an
alternate version of a transition member.
[0032] FIG. 22 depicts a transverse, cross-section view of a
medical device taken along reference 3-3 of FIG. 16 illustrating an
alternate version of a transition member.
[0033] FIG. 23 depicts a longitudinal, cross-section view of an
alternate version of a medical device having an extendable cutting
member coupled with a shaft member shown in an extended
position.
[0034] FIG. 24 depicts a longitudinal, cross-section view of the
extendable cutting member of FIG. 23 shown in a retracted
position.
[0035] FIG. 25 depicts a perspective side view of a delivery system
for an inflatable device.
[0036] FIG. 26 depicts a perspective side view of an alternative
version of a delivery system for an inflatable device.
DETAILED DESCRIPTION OF THE INVENTION
[0037] Referring to FIG. 1, disclosed is one version of a trocar
and cannula assembly (10) of a vertebral cavity formation and
fracture reduction system and method used to access a vertebral
body. The assembly (10) includes a trocar (12) and a cannula (14)
associated with a composite or two-part handle (16). The two-part
handle (16) is configured for rotation and includes a first
detachable handle portion (18) coupled to the trocar (12) and a
second handle portion (20) coupled to the cannula (14). Rotation of
the handle (16) and/or trocar and cannula assembly (10) may be
accomplished in any suitable manner such as with manual rotation or
with a motor. The handle (16) is shown as being symmetrical;
however, any suitable offset or asymmetrical shape is contemplated.
The two-part handle (16) has a distal surface (17) that is gripped
by a user's fingers and a proximal surface (19) that is gripped by
the user's palm. The distal surface (19) of the two-part handle
(16) may have any suitable surface effect such as, for example,
defined finger grips, a curved surface, a generally flat surface,
concavities, and/or convexities. The proximal surface (19) on the
first detachable handle portion (18) may include a surface (21)
configured to accept a hammer strike.
[0038] The distal tip (25) of the trocar (12) is configured to
access and penetrate the cortical bone of a vertebra, where the
vertebra is accessed with the trocar and cannula assembly (10)
engaged. Once the vertebra has been accessed by the distal tip (25)
of the trocar (12), the cannula (14) may be urged into the passage
formed by the trocar (12). The trocar (12), which may be configured
from stainless steel, is removable from the cannula (14) after
accessing the vertebra Removal of the trocar (12) from the assembly
(10) leaves the cannula (14) in place, for example, within the
cortical wall of the vertebra as an instrument conduit for the
insertion of any suitable instrument or device. In the illustrated
version, the trocar (12) is withdrawn from the cannula (14) by
removing the first detachable handle portion (18) from the assembly
(10) until the trocar (12) is pulled proximally from the cannula
(14). The trocar (12) and cannula (14) are shown in more detail in
FIGS. 2 and 3.
[0039] Referring to FIG. 2, one version of the trocar (12) is shown
after removal from the cannula (14) of the assembly (10). The
trocar (12) includes an elongate cylindrical body (22) having a
proximal end and a distal end, where the proximal end of the body
(22) is coupled with the first detachable handle portion (18) and
the distal end includes the distal tip (25), shown in FIG. 1, a
first penetration member (24), and a second penetration member
(26). In the illustrated version, the first detachable handle
portion (18) includes a grip (28) to facilitate rotation of the
penetration members (24) and (26) to access the vertebra and create
a passage into the vertebra. The grip (28) may also be used to
facilitate decoupling the handle portion (18) from the two-part
handle (16). The handle portion (18) further includes a coupling
(30) configured to detachably engage the second handle portion (20)
associated with the cannula (14). Uncoupling the handle portion
(18) from the handle portion (20) allows the trocar (12) to be
removed from the cannula (14).
[0040] The first penetration member (24) of the trocar (12) is a
cylindrical body having a plurality of intersecting flats, bevels,
or faces that form a point at the distal tip (25) configured to
penetrate tissue and vertebral bone with manual rotation and
longitudinal articulation. The first penetration member (24) is
configured to provide the initial access, after an incision is
made, through a patient's skin and into the cortical bone of a
vertebra. The relatively small diameter of the first penetration
member (24) facilitates insertion and positioning or repositioning
of the trocar (12). The second penetration member (26) is a
transition between the smaller diameter first penetration member
(24) and the larger diameter body (22) of the trocar (12) and
includes a plurality of flats configured to expand the diameter of
the passage. In one version, the wider second penetration member
(26) has sharp edges that facilitate cutting of bone. Providing
dual diameter or stepped tips may ease insertion and improve the
stability of the trocar (12). The stepped penetration members (24)
and (26) increase the size of the access point to a diameter
sufficient to accept the cannula (14) for insertion and retention
within the vertebra.
[0041] It will be appreciated that the trocar (12) may be
configured with any suitable features to facilitate vertebral
access, skiving, penetration of cortical bone, or any other
suitable use. The trocar (12) may include one or a plurality of
stepped tips, including the first and second penetration members
(24) and (26), having any suitable cutting effects, diameters,
shapes, and/or configurations. The one or a plurality of
penetration members may be sharp, dull, fluted, or have any other
suitable configuration. The distal end of the trocar (12) may be
tapered, have movable cutting members, or may be coated or
otherwise associated with materials, such as diamond, that
facilitate cutting.
[0042] Referring to FIG. 3, the cannula (14) is shown after removal
of the trocar (12) from the assembly (10) shown in FIG. 1.
Generally, the cannula (14) is configured to function as an
instrument conduit to the intervertebral space, or any other
suitable tissue space, after the initial access point has been
formed and the trocar (12) removed. The cannula (14) may be
retained within the vertebral cortical bone for the duration of the
procedure while the second handle portion (20) remains outside the
patient's body as an access port. The cannula (14) includes an
elongate cylindrical body (32) defining a lumen having a proximal
end and a distal end, where the proximal end of the body (32) is
coupled with the second handle portion (20) and the distal end
includes an aperture (34) through which the trocar (12) and other
instruments are configured to pass. The second handle portion (20)
includes a coupling (36) configured to engage the coupling (30) of
the first detachable handle portion (18), shown in FIG. 2, in a
rotating snap fit. The second handle portion (20) includes a bore
similarly sized and coaxial with the lumen of the cylindrical body
(32) to accept instrumentation. The cannula (14) further includes a
grip (37) that facilitates positioning and removal of the cannula
(14) once the trocar (12) is removed. The grip (37) may be separate
and distinct from the distal surface (17) of the two-part handle
or, alternatively, when the two-part handle (16) is coupled in the
assembly (10) the grip (37) and distal surface (17) may form a
contiguous or substantially contiguous surface. In this manner, the
grip (37) and the distal surface (17) may both be used for rotation
of the handle (16) to facilitate vertebral access. Providing a
two-part handle having a contiguous grip (37) and distal surface
(17) may facilitate use of the assembly (10), shown in FIG. 10,
while providing effective gripping surfaces for use of the cannula
(14) and trocar (12) separately.
[0043] Referring to FIG. 4, one version of a drill (40) is shown
that is used in accordance with a vertebral cavity formation and
fracture reduction system and method. The drill (40) includes an
elongated, stainless steel cylindrical body (42) having a distal
end and a proximal end, where the proximal end is coupled to a
handle (44) and the distal end is configured as a drill bit (46).
The body (42) of the drill (40) is sized to fit through the central
lumen of the cannula (14) and, after introduction into the cannula
(14), the drill bit (46) is used to form, for example, an access
passage in the cancellous bone of the vertebra. The handle (44) is
provided with a grip (48) to facilitate manual rotation of the
drill (40) within the cancellous bone of the vertebra to form a
passage up to the anterior cortex. The body (42) is provided with
markings (50) to indicate the minimum depth required for the
insertion of subsequent instruments. Following creation of the
access passage, the drill (40) is configured for removal through
the cannula (14). Any suitable markings (50) may be provided using
any suitable metric to determine proper insertion.
[0044] Referring to FIG. 5, disclosed is one version of an
articulating cavity formation instrument (100) that may be used to
form a tissue cavity in, for example, cancellous bone within a
vertebral body. In one version, the cavity formation instrument
(100) is approximately 40 cm in length and includes, generally, a
handle (102), an insertion member, such as insertion tube (104),
and an end effector (106) configured for articulation. The handle
(102) has a generally cylindrical body, having a proximal end and a
distal end, aligned along a first linear axis A-A. The handle (102)
includes a body (108) and a series of rotational actuation members
(110), (112), and (114), that are rotatable about the first linear
axis A-A to articulate various aspects of the end effector (106).
In the illustrated version, the rotational members (110) and (112)
are knobs secured to the center shaft (128), shown in FIG. 6, and
are retained within the body (108) of the handle (102). Rotational
member (114) is secured to the body (108) of handle (102) by a
mating flange. It will be appreciated that the illustrated
rotational actuation members (110, (112), and (114) are described
by way of example only, where any suitable mechanism, such as
slides, levers, geared components, or the like, including
combinations thereof, may be used to actuate the cavity formation
instrument (100).
[0045] The insertion tube (104) of the vertebral cavity formation
and fracture reduction system extends axially along the first
linear axis A-A from the distal end of the handle (102) to the
proximal end of the end effector (106). The insertion tube (104)
may be stainless steel and defines an interior lumen having an
opening at both ends. In the illustrated version, with particular
reference to FIG. 8, a pivot pin (116) is welded to the insertion
tube (104), where the pivot pin (116) is transverse to and offset
from the first linear axis A-A. As will be described herein, the
pivot pin (116) facilitates articulation of the end effector (106)
such that it is offset from the first linear axis A-A. The pivot
pin (116) is one example of an articulation region of the
instrument (100)
[0046] The end effector (106), which has a proximal portion (122)
and a distal portion (124), is located at the distal end of the
insertion tube (104) and is configured to rotate and articulate
relative to the insertion tube (104). The proximal portion (122) of
the end effector (106) is coupled to the insertion tube (104) with
the pivot pin (116) such that the end effector (106) is restrained
from axial movement relative to the insertion tube (104), but is
rotatable about the pivot pin (116). In this manner, the end
effector (106) can be articulated such that it is offset from first
linear axis A-A into alignment, for example, with the second linear
axis B-B. The second linear axis B-B is described by way of example
only, where any suitable degree or distance of articulation is
contemplated.
[0047] The distal portion (124) of the end effector (106) which may
be, for example, from 1.8 cm to 2.8 cm in length, is configured to
rotate, relative to the proximal portion (122) of the end effector
(106), about the central axis A-A of the end effector (106). The
distal portion (124) of the end effector may also be rotated about
the second linear axis B-B, or any other suitable offset axis, when
the end effector (106) is in an articulated position. Rotation of
the end effector (106), in both the articulated and unarticulated
position, facilitates cavity formation by allowing cancellous bone
to be cut about or around multiple axes. Providing a wide range of
axes about which portions of a cavity can be formed facilitates the
creation of a wide range of cavity configurations that may provide
greater therapeutic effect.
[0048] The end effector (106) further includes a lateral aperture
(120) and an aperture (134) through which a deformable cutter (118)
is extended and retracted. In the illustrated version, the
deformable cutter (118) is an elongate, stainless steel flexible
band that may be between 1.5 cm to 3 cm in length; however, any
suitable cutting element such as, for example, a wire, an energized
cutting element, a filament, a cutting element having a free end, a
cutting element having memory retention properties, and/or a
cutting element that expands outwardly with rotation may be
utilized. Any suitable shape such as oval, triangular, or
elliptical is contemplated. In the illustrated version, the distal
end of the cutter (118) is fixedly coupled to the end effector
(106) and the proximal end of the cutter is attached via a junction
member (132) to a movable shaft (128) configured to rotate and
translate within the insertion tube (14). The cutter (118) is
threaded through the aperture (134) in the distal end of the end
effector (106) and is fixedly coupled to a more proximal portion of
the end effector, as illustrated in FIG. 8, to form an expandable
and retractable cutter.
[0049] FIGS. 6-8 illustrate longitudinal, cross-section views of
the cavity formation instrument (100) of the vertebral cavity
formation and fracture reduction system and method. FIG. 7
illustrates a more detailed view of the handle (102) and FIG. 8
illustrates a more detailed view of the end effector (106).
Referring to FIGS. 6 and 7, a central channel (126) is depicted
that extends along the first linear axis A-A within the body (108)
of the handle (102). The proximal end of the insertion tube (114)
is affixed within this channel (126) such that the insertion tube
(104) and the channel (126) are coaxial. A shaft (128) is provided
that extends from a coupling with the rotational member (114)
through the interior lumen of the insertion tube (104) to a
coupling at the junction member (132) associated with the distal
portion (124) of the end effector (106).
[0050] Referring to FIG. 7, the shaft (128) is associated with the
rotational member (114) such that rotation of the rotational member
(114) correspondingly rotates the shaft (128) and the attached
distal portion (124) of the end effector (106). Thus, the
rotational member (114) is used to rotate the end effector (106)
and cutter (118) relative to the insertion tube (104). In the
illustrated version, the rotational member (114) and the shaft
(128) are not coupled for axial translation, only rotational
translation, where axial translation of the shaft (128) is
independent from the operation of the rotational member (114). The
rotational member (114) is used to rotate the end effector (106)
when the cutter (118) is extended to rotationally cut tissue to
form a tissue cavity, for example, wholly within a vertebra.
[0051] Referring to FIG. 7, the center rotational member (112) is
associated with the shaft (128) to facilitate expansion and
retraction of the cutter (118) through the aperture (134). The
rotational member (112) is threadedly engaged with the shaft (128)
in a jack screw configuration such that rotational movement of the
rotational member (112) is translated as axial movement to the
shaft (128). The shaft (128) is freely rotatable relative to the
rotational member (112) such that only axial motion, and not
rotational articulation, is translated to the shaft (128) by the
rotational member (112). As discussed previously, rotation of the
shaft (128) may be controlled independently by the proximal
rotational member (114). The rotation and axial translation of the
shaft (128), in the illustrated version, are distinct and separate
operations with independent mechanisms to give the cavity formation
instrument (100) operational flexibility.
[0052] Referring to FIG. 8, axial translation of the shaft (128)
causes the junction member (132) to urge the proximal end of the
cutter (118) in a corresponding proximal or distal direction.
Translating the shaft (128) in the distal direction, such as by
rotating the rotational member (112) in a first direction, urges
the cutter (118) against an abutment (138) and outwardly through
the aperture (134), thus expanding the cutter outwardly to increase
the cutting radius. Translating the shaft (128) in the proximal
direction, such as by rotating the rotational member (112) in a
second direction, urges the cutter (118) to retract through the
aperture (134) and against a transverse member, thus reducing the
cutting radius. The rotational member (112), shown in FIG. 7, can
be used to adjust the cutting radius of the cavity formation
instrument (100) to a desired radius prior to rotating the cutter
(118) to form a cavity. In an alternate version, the cutter (118)
can be extended or retracted simultaneously while rotating the end
effector (106) to form a cavity.
[0053] Referring to FIG. 7, the distal rotational member (110) is
associated with an articulation drive member (130) to facilitate
articulation of the end effector from the first linear axis A-A to
the second linear axis B-B, shown in FIG. 9. The rotational member
(110) is threadedly engaged with the drive member (130) in a jack
screw configuration such that rotational movement of the rotational
member (110) is translated as axial movement to the drive member
(130). The distal end of the drive member (130) is coupled to
proximal portion (122), shown in FIG. 8, of the end effector (106)
with a pin (136). Drawing the drive member (130) and pin (136)
proximally causes the end effector (106) to rotate about the pivot
pin (116). Articulating the end effector (106) in such a manner
allows the end effector to be positioned along a second linear axis
B-B, shown in FIG. 9, offset from the first linear axis A-A. When
in the offset position, the cutter (118) may be extended with the
rotational member (112) and rotated with the rotational member
(114) to increase the volume of a cavity. The end-effector (106) is
realigned with the first linear axis B-B by urging the drive member
(130) and pin (136) distally.
[0054] FIG. 9 illustrates a longitudinal, cross-sectional view of
the end effector (106) shown in the articulated position with the
cutter (118) extended. The end effector (106) has been articulated
into alignment with the second linear axis B-B by axially
translating the drive member (130) and rotating the end effector
(106) about the pivot pin (116). Articulation of the end effector
(106) may occur at any suitable articulation region or point such
as, for example, the pivot pin (116), a geared articulation region,
a hinge, a metal hinge, a plastic material, a flexible member, a
living hinge in flexible material, a shape memory alloy
articulation region, or combinations thereof. One or a plurality of
articulation regions or points, such as pivot pins (116), may be
provided to allow for articulation about multiple planes and/or
axes. Articulation may be mechanical, such as with a pivot pin or a
geared configured, in a manner that excludes flexible or living
hinge components at the articulation point or region. As described
in the illustrated version, the drive member (130) is proximally
and distally translated by rotating the rotational member (110).
The cutter (118) is shown in the extended position after the shaft
(128) has been urged distally by rotating the rotational member
(112). In the position shown in FIG. 9, the distal portion (124) of
the end effector (106) is rotated to form a cavity portion about
the second linear axis B-B.
[0055] Articulation of the end effector (106) allows for an offset
cavity portion to be formed while the insertion tube (104) remains
aligned with the first linear axis A-A. The offset cavity portion
of the intervertebral cavity facilitates central placement of the
balloon (212), which may be advantageous under certain
circumstances. For example, an offset cavity may be useful
depending on the geometry of the bone, in creating an anchor to
provide more torque in an asymmetrical cavity, creating an
undercut, or for accessing regions of a bone offset from the access
point. Creating an offset cavity may allow for larger cavities to
be created. Generally, the range of cavities and access may be
increased while permitting the instrument to be inserted through a
relatively small access point.
[0056] Referring to FIG. 10, disclosed is one version of a
vertebral fracture reduction apparatus (200) of the vertebral
cavity formation and fracture reduction system. The vertebral
fracture reduction apparatus (200) is approximately 32 cm in length
and includes, generally, a series of flexible access ports (202),
(204), and (206), a port housing (208), an insertion sheath (210),
a central dual lumen (218), a side lumen (220), an inflatable
member or balloon (212), and a delivery tentacle (214). The
apparatus (200) is configured for insertion into a cut vertebral
cavity in a deflated configuration and for expansion within the
cavity to reduce a vertebral compression fracture. Once the
fracture is reduced, the apparatus (200) is configured to deliver
bone cement into the vertebral cavity to restore the integrity of
the vertebra. Any suitable dimension may be provided where, for
example, the apparatus (200) may be any length sufficient to reach
a target site without interfering with a fluoroscope.
[0057] FIG. 11 illustrates a longitudinal, cross-sectional view of
the vertebral fracture reduction apparatus (200) of the vertebral
cavity formation and fracture reduction system. FIG. 12 illustrates
a more detailed view of the handle access ports (202), (204),
(206), and port housing (208). FIG. 13 illustrates a more detailed
view of the balloon (212) and delivery tentacle (214). FIG. 14 is a
cross-sectional view of the delivery lumen and insertion sheath.
Referring to FIGS. 11 and 12, the aligned access ports (202),
(204), and (206) have a coplanar orientation and each include a
luer connection configured to engage a single-plunger delivery
syringe. Access ports (202) and (204) are associated with the
central dual lumen (218) and the access port (206) is associated
with the side lumen (220). Any suitable type or number of ports may
be provided where, for example, the ports may be configured to
prevent accidental use of an incorrect syringe or applicator with
color coding, varying dimensions, varying connections, or the like.
Any suitable delivery apparatus may be used including syringes,
screw-type plungers, push plungers, pistol plungers, pressurized
devices, motorized pumps, or the like.
[0058] Referring to FIGS. 10 and 11, in the illustrated version the
central dual lumen (218) is an elongated, semi-rigid cylindrical
body that is extruded with bismuth, a radiopaque additive, to
facilitate visualization during surgery. The dual lumen (218) is
associated with access ports (202) and (204) and extends from the
housing (208) through the balloon (212) and distally from the end
of the balloon. The dual lumen (218) passing through the balloon
(212) may also be referred to as one version of a tentacle for
delivering a flowable material. In the illustrated version, the
dual lumen (218) is non-linear and has a substantially S-shaped or
curved distal end about which the balloon (212) is mounted.
Substantially linear versions or other orientations for the dual
lumen (218) are contemplated. With particular reference to the
cross-sectional view of FIG. 14, the dual lumen (218) includes a
saline delivery lumen (222) and an adjacent cement delivery lumen
(224) in a parallel configuration. The saline delivery lumen (222)
is fused at the distal end just proximal to the distal end and
includes one or a plurality of apertures (216) that establish fluid
communication with the internal cavity of the balloon (212). The
saline delivery lumen (222) provides fluid communication between
the access port (202) and the balloon (212) such that saline
delivered through the access port (202) enters, fills, and expands
the balloon (212). Similarly, saline withdrawn through the access
port (202) correspondingly deflates the balloon (212). In the
illustrated version, saline delivered through the access port (202)
into the balloon (212) is used solely for balloon inflation and is
not released into the vertebra or any other part of the body.
However, saline may be released or delivered into a vertebral body,
for example, to assist is clearing away cancellous bone from the
cortical wall.
[0059] Although inflation of the balloon (212) is described with
reference to saline, it will be appreciated that any suitable
flowable material or fluid, which includes air or gases, may be
used to inflate and/or deflate the balloon (212). For example, bone
cement, biologic material, bone growth materials, bone fragments,
bone paste, bone gel, saline, saline mixed with radiopaque
additives, pressurized air, or combinations thereof may be
utilized. The balloon (212) may be non-porous, semi-porous, or
porous where, for example, a porous balloon filled with bone cement
may ooze bone cement into a vertebral cavity during inflation.
[0060] It will be appreciated that the dual lumen (218) may have
any suitable configuration and any suitable number of lumens
passing entirely or partially therethrough. The dual lumen (218)
may extend through the balloon (212) as illustrated or,
alternatively, the dual lumen (218) may be adjacent or set apart
from the balloon (212). The saline delivery lumen (222) and the
cement delivery lumen (224) may be configured as separate lumens
not retained within a single dual lumen (218). Generally, all
lumens may be single lumen or multi-lumen tubing, where multi-lumen
tubing may provide an advantageous drop in internal diameter by
sharing a wall. Additional lumens may be provided, for example, for
suction, irrigation, a guidewire, inflation of additional
inflatable members or cement containers, or for tamping.
[0061] Still referring to FIGS. 10, 11, and 14, the cement delivery
lumen (224) extends along the length of the dual lumen (218) and
terminates in a distal aperture (226) at the distal end of the
reduction apparatus (200). The cement delivery lumen (224) is in
fluid communication with the access port (204) such that cement
delivered through the access port (204) exits the apparatus (200)
at the distal aperture (226). The access port (204) and cement
delivery lumen (224) are configured to deliver bone cement, or any
other suitable material, through the reduction apparatus (200) into
a vertebral body cavity to, for example, restore the strength of
the vertebra after fracture reduction. In the illustrated version,
the access port (204) and the cement delivery lumen (224) are
configured in such a manner that instruments, such as tamping
instruments, cannot be inserted into the lumen (224); however, it
will be appreciated that the access ports can be configured to
accept tamping instruments, or the like, to facilitate expelling
materials from within the lumens, packing materials into the
vertebral body, and/or capping the access point to the vertebra
after inserting filler material. Providing a separate port
configured to accept a tamping, capping, or packing instrument is
also contemplated.
[0062] Referring to FIGS. 10 and 11, in one version, the side lumen
(220) is an elongate PET tube in fluid communication with the
access port (206) that terminates in a delivery tentacle (214). In
the illustrated version, there is a single delivery tentacle (214)
made from PET that is integral and in fluid communication with the
side lumen (220). With particular reference to the cross-sectional
view of FIG. 14, the side lumen (220) may be bonded with a UV
curable adhesive to the dual lumen (218) and the balloon (212),
where both the dual lumen (218) and the side lumen (220) may be
surrounded by an elongate sheath (210) that extends from the
housing (208) to just proximate the balloon (212). The dual lumen
(218) may be bonded to the sheath (210) with cyanoacrylate. The
delivery tentacle (214), which may be the portion of the side lumen
(220) that projects from the sheath (210), can be bonded to the
anterior side of the outer surface of the balloon (212) with UV
curable adhesive. The delivery tentacle (214) includes a plurality
of spaced apart apertures along the length of the tentacle through
which cement is delivered into a vertebral cavity.
[0063] It will be appreciated that the illustrated lumens (218),
(210) may be bonded or retained by any suitable means, such as the
sheath (210), as illustrated, or any suitable adhesive. The
delivery tentacle (214) and side lumen (220) may be a contiguous
structure, as shown, or, alternatively, the delivery tentacle may
be a separate component affixed, coupled, or otherwise attached to
the side lumen (220). The side lumen (220) may be rigid and the
tentacle (214) may be flexible, both may be flexible, or both may
be rigid or semi-rigid. The delivery tentacle (214) further
comprises one or a plurality of tentacles having any suitable
configuration for the delivery of bone cement, dye, gas, filling
agent, therapeutic agent, medicament, and/or any other suitable
material. The delivery tentacle (214) may be provided with one or a
plurality of apertures and/or may be constructed from a porous
material for the delivery of fluid into a vertebra.
[0064] Referring to FIGS. 10, 11, and 13, in the illustrated
version the balloon (212) is a non-porous PET structure, having a
generally uniform wall thickness, positioned near the distal end of
vertebral fracture reduction apparatus (200). The balloon (212) is
coated with urethane and tungsten powder. Each end of the balloon
(212) is bonded to the dual lumen (218) to form a fluid-tight seal
during inflation. A length of the balloon (212) at each end is
bound to the dual lumen with a strap to help maintain the integrity
of the bond during inflation. The illustrated balloon (212) has a
non-axisymmetric configuration and is not aligned about any linear
axis. The balloon (212) defines a single internal cavity and is not
compartmentalized. In the illustrated version, the balloon (212)
does not have any internal restraints or external restraints that
restrain expansion of the balloon. The proximal and distal regions
of the balloon (212) have a greater width than the central portion
of the balloon (212), and each end region tapers towards the
coupling with the dual lumen (218). The balloon (212) is configured
for fluid communication with the access port (202) and the saline
delivery lumen (222) such that the balloon (212) may be inflated to
reduce a vertebral bone fracture when expanded against cortical
bone endplates.
[0065] The balloon (212) may be provided with any suitable features
or elements configured to restrain, shape, or otherwise configured
the balloon (212) including, for example, internal restraints,
external restraints, varying wall thicknesses, bands, and/or
variations in material. Although the balloon (212) is shown in a
non-axisymmetric configuration, the balloon may have an
axisymmetric configuration, or any other shape, and may be aligned
along a linear axis. The ends of the balloon (212) may be tapered,
as shown, or may be inverted or have any other suitable
configuration. Providing a balloon having a uniform diameter along
the length thereof is also contemplated. Any suitable partial or
complete coating in one or a plurality of layers may be utilized
including coatings that are lubricious, rough for trauma
applications, radiopaque, anti-bone growth, non-adhesive, barium,
bismuth, PET, materials embedded in PET, tungsten powder, tantalum,
or combinations thereof. Additionally, radiopaque coatings may be
masked in certain sections to aid in visualization, measurement,
trauma, placement, guidance, or the like. Any suitable region,
band, design, marking, indicia, or writing may be masked or
otherwise indicated for visualization.
[0066] Referring to FIG. 15, disclosed is one version of a method
(300) for use of the vertebral cavity formation and fracture
reduction system. The method comprises Providing a Trocar and
Cannula Assembly Step (301) that includes providing, for example,
the trocar and cannula assembly (10) described with reference to
FIGS. 1-3. The method (300) comprises Accessing a Vertebral Body
With the Trocar and Cannula Assembly Step (302). Step (302)
includes making a small incision in the skin of a patient and
inserting the trocar and cannula assembly (10) through the skin and
adjacent a fractured vertebra with, for example, a trans-pedicular
approach, a postero-lateral approach, or a trans-sacral axial bore
approach. The vertebra is accessed initially, through, for example,
the pedicle or cortical bone, with the first penetration member
(24) of the trocar (12). The first penetration member (24) is
configured with a small point at the distal end to facilitate the
introduction of the trocar (12) into the pedicle, or other
location, to allow for repositioning if needed, and to provide
control in positioning the trocar. The small point of the first
penetration member (24) is used to penetrate the pedicle until the
second penetration member (26) abuts the pedicle. The larger
diameter second penetration member (26) is then bored into the
pedicle to form an access point sufficiently large for insertion of
the cannula (14). After the access point is created by the trocar
(12), the cannula (14) is retained within the access point to
function as an instrument conduit for the duration of the
procedure. Steps (301)-(303) are described with reference to a
composite trocar and cannula assembly (10); however, it will be
appreciated that any suitable trocar and/or cannula may be used in
accordance with versions herein.
[0067] With the cannula (14) in place, the method (300) comprises
Removing the Trocar from the Cannula Step (303), which includes
withdrawing the trocar (12) proximally from the cannula by
uncoupling the two-part handle (16) and withdrawing the first
removable handle portion (18). Removing the handle portion (18) and
the attached trocar (12) from the lumen of the cannula (14) leaves
behind a hollow lumen through which a drill (40), shown in FIG. 4,
a cavity formation instrument (100), shown in FIG. 5, a vertebral
fracture reduction apparatus (200), shown in FIG. 10, and/or any
other suitable instrumentation, may be inserted. Upon removal of
the trocar (12), the cannula (14) is left in place within the
vertebra where it will remain for the duration of the procedure.
Other instruments that may be inserted include a backup cement
delivery tube, suction, a biopsy device, a camera, a scope, a bone
remover, or a cement stopper.
[0068] The step of Providing a Drill Step (304) includes providing
a passage creating instrument, such as the drill (40), which is
described with reference to FIG. 4. The step of Drilling an Access
Passage in Vertebral Cancellous Bone Step (305) includes inserting
the passage creating instrument or drill (40) into the cannula (14)
until the drill (40) abuts vertebral bone. In one version, the
drill bit (46) of the drill (40) is then manually rotated to form a
substantially linear cylindrical passage into the vertebral
cancellous bone up to the anterior cortex. The depth of the passage
is measured by the markings (50) on the body (42) of the drill (40)
to guide the surgeon in controlling the creation of the passage. In
one version, the handle (44) of the drill (40), which projects
proximally from the second handle portion (20) of the cannula (14),
is manually rotated by the surgeon's hand via the grip (48) to form
the desired passage. Step (305) further includes removing the drill
(40) from the cannula (14) after creation of the passage. It will
be appreciated that manual operation of various instrumentation
described herein can be performed with a motor or by other
electrical or mechanical means.
[0069] The step of Providing a Cutting Instrument Step (306)
includes providing a cavity formation instrument or device such as
the cavity formation instrument (100) described with reference to
FIGS. 5-9. The step of Positioning the Cutting Instrument Within
the Access Passage Step (307) includes inserting the cavity
formation instrument (100) through the lumen of the cannula (14)
into the passage created by the drill (40). During insertion, the
cavity formation instrument (100) is maintained in a linear
position where the end effector (106) is aligned with the first
linear axis A-A. The flexible cutting element (118) is in the fully
retracted position to minimize the width of the end effector (106)
during insertion. The depth and placement of the cavity formation
instrument (100) may be monitored via fluoroscope along with depth
markings to properly position the end effector (106) within the
access passage of the vertebra. In one version, the end effector is
positioned such that it is entirely within the cancellous bone
volume of a single vertebra. It will be appreciated that methods
described herein may also be used for tissue cavity formation,
orthopedic cavity formation, spinal cavity formation, vertebral
cavity formation, discectomies, or other orthopedic or medical
procedures.
[0070] The step of Laterally Extending a Flexible Cutting Element
of the Cutting Instrument Step (308) includes laterally extending
the cutter (118) away from the end effector (106). In one version,
the cutter (118) is laterally extended by manually rotating the
rotational member (112) in a first direction. Manual rotation of
the rotational member (112) operates as a jack screw to urge the
shaft (128) distally. Distal translation of the shaft (128), which
is coupled with the cutter (118) via the junction member (132),
urges the cutter (118) outward through the aperture (134). Because,
in the illustrated version, the cutter (118) is fixed at one end to
a proximal portion of the end effector (106), the cutter (118) is
expanded outwardly to form an arcuate shape as the shaft (128) is
urged distally. Step (308) includes laterally extending the arcuate
shape of the cutter (118) a desired distance as determined by
fluoroscope or by resistance from the access passage.
[0071] The step of Cutting a First Vertebral Cavity Portion Step
(309) includes forming a cavity within the cancellous bone of a
vertebra using the cutting instrument (100). Following Step (308)
where the cutter (118) is partially laterally extended, the end
effector (106) may be rotated about the first linear axis A-A to
cut cancellous bone tissue. In one version, the cavity is formed by
manually rotating the rotational member (114), which
correspondingly rotates the shaft (128) and end effector (106) to
cut into cancellous bone. The cavity formed in Step (309) may be
generally axisymmetric about the first linear axis A-A. The cavity
may have a greater width than the drilled access passage. In one
version, the Steps (308) and (309) are performed simultaneously to
extend the cutting element (118) while rotating the end effector
(106) to form a cavity. Although described with reference to
forming a vertebral cavity, it will be appreciated that a cavity
forming instrument described in accordance with methods herein may
be used in any suitable orthopedic or medical application such as,
for example, to form cavities in long bones or in cardiovascular
applications for plaque removal. Other applications include
vertebral disc applications, neurosurgery, interventional
radiology, and pain management.
[0072] Step (309) further includes extending the cutter (118)
laterally at increments to form successively larger cavities. The
cutter (118), may be extended as described with reference to Step
(308), is used to cut a portion of a cavity as described above. In
one version, the cutter (118) is then incrementally extended
radially outward via rotation of the rotational member (112). The
rotational member (114) is then rotated to form a successively
larger cavity. The incremental extension of the cutter (118) with
subsequent cavity formation via the rotational member (114) is
repeated a sufficient number of times to create the desired cavity.
A suitable cavity size is determined via fluoroscope. During cavity
creation, as the cancellous bone is cut it may be allowed to
collect, gather, or pool within the vertebra, it may be compacted
against the cortical wall, and/or it may be removed from the
vertebra. A suction device may be provided to remove pieces of bone
and/or a compaction device may be provided to compact bone against
the cortical wall to clear cancellous bone from the cavity.
[0073] The step of Articulating the Distal End of the Cutting
Instrument Step (310) includes articulating the end effector (106)
of the cutting instrument (100) within the cavity formed in
accordance with Step (309) such that it is offset from the first
linear axis A-A. The end effector may be offset such that it is
aligned with a second linear axis such as axis B-B. The
articulation may occur at one or a plurality of articulation points
or regions, where the end effector (106), for example, may be
articulated such that it is offset a first distance from the axis
A-A. The first distance may be achieved by pivoting the end
effector (106), bending the end effector (106), or otherwise
articulating the end effector (106) such that it is offset,
pivoted, or spaced apart from the axis A-A. Step (310) includes
partially retracting the cutter (118) such that it is adjacent the
end effector (106) prior to articulation. The end effector (106)
may then be articulated by rotating the distal rotational member
(110) in a first direction as described herein.
[0074] In one version, articulation in accordance with Step (310)
is accomplished by incrementally articulating the end effector
(106) toward the opposite side of the intervertebral space of the
vertebral body. The rotational member (10) is rotated in a first
direction to urge the end effector (106) such that it is
incrementally offset from the first linear axis A-A. The rotational
member (114) is then rotated to increase the size of the cavity to
provide more space for the articulation of the end effector (106).
The rotational member (110) is again rotated in the first direction
to further articulate the end effector (106) incrementally before
again rotating the end effector via the rotational member (114).
The incremental articulation of the end effector (106) with
subsequent cavity formation via the rotational member (114) is
repeated a sufficient number of times, as needed, until the end
effector (106) is sufficiently articulated. Alternatively, rotation
and articulation may be performed simultaneously. The end effector
(106) is properly guided by the surgeon to the central position via
fluoroscope. Articulating the end effector (106) towards the
opposite side of the vertebral body may allow a cavity to be formed
that exposes the cortical endplates for direct contact with the
balloon (212) during expansion to reduce a vertebral compression
fracture. Once positioned, the end effector (106) may be aligned
along a second linear axis B-B angled away from the first linear
axis A-A of the insertion tube (104).
[0075] The step of Cutting a Second Vertebral Cavity Portion Step
(311) includes expanding the cavity portion formed in accordance
with Step (309), for example, to expose regions of cortical bone
within the intervertebral space. The second cavity portion is
formed, in one version, by laterally extending the cutter (118) and
rotating the cutter (118) in the stepwise manner as described in
accordance with Steps (308) and (309) to expose the end plates of
the vertebra. Alternatively, these can be actuated simultaneously.
As with Steps (308) and (309), the cutter (118) may be guided via
fluoroscope. Specifically, the formation of the second cavity
portion may form a central cavity that exposes the endplates of the
vertebral cortical bone that will serve as the foundation for
expansion of the fracture reduction balloon (212).
[0076] In one version, as the endplates are exposed, the cutter
(118) may form a pocket within the cancellous bone adjacent the
anterior wall of the vertebral body. When a fracture reduction
procedure is performed with the patient lying face down, there is a
natural tendency for cut cancellous bone to be drawn away from the
intervertebral space into the anterior pocket of the cavity. In
this manner, the anterior pocket of the cavity may be used as a
cancellous bone reservoir that obviates the need for bone
compaction or bone removal to access the end plates. Step (311)
comprises cutting cancellous bone away from the endplates of a
vertebra and allowing the cut cancellous bone to collect in the
anterior pocket of the cavity. Cutting away cancellous bone, rather
than compacting the cancellous bone, provides for an exposed
cortical surface that may be more responsive to more predictable
compression forces. Removing as much cancellous bone as possible
from the intervertebral body adjacent the endplates may increase
the predictability and control of the procedure.
[0077] Although a method of cutting and collecting cancellous bone
is described, it will be appreciated that cancellous bone may be
removed, pooled, condensed, and/or compacted to form a cavity or
cavity portion in accordance with versions herein. For example,
cutting away a portion of the cancellous bone and then compacting a
thin region of cancellous bone may act as a seal within the
vertebral body to prevent the leakage of bone cement or other
fluid. By cutting away a first portion of cancellous bone, prior to
compacting a second region of cancellous bone, sufficient
cancellous bone may be removed such that a fracture reduction
device is sufficiently adjacent the cortical bone of the vertebra
to effectively reduce a fracture. Thus, numerous techniques may be
combined in forming a desired cavity. Multiple accessing, cutting,
tamping, compaction, stoppering, curing, removal, suction, and/or
expansion devices may be inserted or otherwise used in any suitable
manner or order.
[0078] The step of Articulating the Distal End of the Cutting
Instrument Step (312) includes articulating the end effector (106)
of the cutting instrument (100) in the return direction until it is
linearly aligned with the first linear axis A-A. The end effector
(106) is articulated into alignment by rotating the distal
rotational member (110) in a second direction. In this manner, the
cutting instrument (100) may be returned to its pre-insertion
linear configuration such that it can be easily removed through the
cannula (14). The step of Retracting the Flexible Cutting Element
Step (313) includes withdrawing the cutter (118) through the
aperture (134) by rotating the rotational member (112) in a second
direction. In this manner, the cutter (118) is returned to its
pre-insertion retracted configuration such that it can be easily
removed through the cannula (14). The step of Removing the Cutting
Instrument Through the Cannula Step (314) includes removing the
cutting instrument (100) through the cannula after the cutter (118)
has been retracted and the end effector (106) has been brought into
linear alignment with the insertion tube (104). In one version, the
cannula (114) is left in place during all Steps in which the
cutting instrument (100) is utilized. It will be appreciated that
any suitable number of cavity formation instruments having any
suitable configuration may be inserted through the cannula (14).
For example, cavity formation devices having a plurality of
articulations or joints and/or varying degrees of articulation may
be utilized. Although the end effector (106) is described as
retaining a substantially linear configuration, it will be
appreciated that the end effector (106) may have any suitable
shape, such as a curved shape, or be deformable such as, for
example, from a substantially linear shape to a curved shape if
made from a shape memory alloy such as a nickel-titanium alloy.
[0079] The step of Providing a Fracture Reduction Apparatus Step
(315) includes providing a fracture reduction apparatus such as the
fracture reduction apparatus (200) described with reference to
FIGS. 10-14. It will be appreciated that Step (315) is described
with reference to the reduction of vertebral fractures by way of
example only and may be used in any suitable tissue application.
The step of Positioning the Fracture Reduction Apparatus Within the
Cavity Step (316) includes inserting the fracture reduction
instrument (200) through the lumen of the cannula (14) into a
cavity created by, for example, the cutting instrument (100). Prior
to insertion, the balloon (212) may be pleated and folded in a
folding machine or otherwise be provided with a reduced size. The
folding machine includes two separate sets of jaws having a
plurality of fingers each, where the first set of jaws heats and
pleats the balloon (212) and the second set of jaws folds the
balloon (212) by wrapping it around the central lumen (218). During
insertion, the fracture reduction apparatus (200) is maintained in
a deflated position to minimize the width of the balloon (212)
during insertion. In one version, the flexibility of the tentacle
(214) during insertion allows for the reduced diameter tentacle
(214) to be inserted through a relatively narrow access passage.
The flexibility of the tentacle (214) then allows for greater
expansion of the tentacle (214) after insertion. The depth and
placement of the fracture reduction apparatus (200) are monitored
via fluoroscope and with depth markings to properly position the
balloon (212) within the cavity of the vertebra.
[0080] After insertion of the fracture reduction instrument, the
substantially S-shaped or curved distal end of the dual lumen (218)
shown in the illustrated version is projected into the vertebral
cavity such that the balloon (212) is centrally located within the
cavity. In one version, the balloon (212) is positioned such that,
upon expansion, the walls of the balloon press against the exposed
endplates of the vertebra after cancellous bone has been removed.
Other versions may compact substantial or minimal amounts of
cancellous bone. The balloon (212) may be constructed from flexible
but substantially inelastic PET such that the balloon (212) expands
only to a predetermined shape regardless of the level of
inflationary pressure. The balloon (212) may be configured to
expand against the cortical endplates to reduce a vertebral
fracture, but not to penetrate the anterior pocket of the cavity
into which the cancellous bone may be collected. Thus, in one
version, the vertebral endplates are expanded to reduce the
vertebral fracture without compacting or removing cancellous bone.
Alternative versions may incorporate removing and/or compacting
cancellous bone.
[0081] The step of Inflating the Fracture Reduction Apparatus to
Reduce a Fracture Step (317) includes inflating the fracture
reduction element (200), for example, against the exposed endplates
of a vertebra to reduce a fracture. In one version, the balloon
(212) is expanded uniformly with the introduction of a flowable
material, such as saline, via the access port (202). In one
version, the flexible but inelastic PET balloon (212) is configured
to expand against the endplates of the vertebra without expanding
to fill the entire cavity. In this manner, the bone fracture is
reduced without compacting the bone retained within the anterior
pocket of the cavity. After being positioned adjacent the endplates
of the vertebra in accordance with Step (316), the balloon (212) is
inflated with a syringe by introducing saline solution through the
access port (202) and saline delivery lumen (222). The inflation of
the balloon (212) corresponds to the volume of saline delivered
through the syringe. A surgeon determines sufficient inflation by
viewing the fracture reduction apparatus (200) under a fluoroscope
and by monitoring the pressure gauge. Because the balloon (212), in
the illustrated version, is constructed from flexible but
substantially inelastic PET, the balloon expands only to its
predetermined shape regardless of the level of inflationary
pressure. The balloon (212) is configured to expand against the
cortical endplates to reduce the fracture, but not to penetrate the
anterior pocket of the cavity into which the cancellous bone has
collected. Thus, in one version, the vertebral endplates are
expanded to reduce the fracture without compacting or removing
cancellous bone.
[0082] It will be appreciated that the balloon (212) may,
alternatively, have an elastic configuration configured to fully
fill a cavity, internal or external restraints to define the shape
of the balloon, any suitable shape, any suitable radiopaque marker,
any suitable surface effect or coating, any suitable number of
chambers, compartments, or layers, and/or any suitable combination
of materials or wall thicknesses. Although the balloon (212) has
been described with reference to vertebral fracture reduction
procedures, it will be appreciated that the methods described
herein may be useful in other medical procedures such as orthopedic
or cardiovascular applications. The balloon (212) may be used to
compact cancellous bone to form a cavity and/or to form a seal
around cortical bone to prevent bone cement or fluid leakage. The
balloon (212) may be filled or inflated with any suitable material
such as saline, bone cement, gas, dye, and/or any other fluid and
may have a porous or non-porous surface. In one version the balloon
(212) is permanently implantable where, for example, the balloon is
inflated with bone cement and left within the vertebra.
[0083] The step of Delivering Bone Cement Into the Cavity Step
(318) includes delivering any suitable flowable material, such as
bone cement, fluid, air, gas, medicament, bone paste, bone pieces,
bone growth factor, or the like, through the cement delivery lumen
(224) and the delivery tentacle (214) via access ports (204) and
(206), respectively. Flowable material is delivered through the
access ports (204) and (206) with a syringe that is manually
plunged. Following Step (317), where the balloon (212) is inflated,
the flowable material is delivered through the tentacle (214) to
fill a portion of the cavity. As the cavity becomes filled with
bone cement, or any other suitable flowable material, the balloon
(212) may be gradually deflated in accordance with Step (319) to
allow bone cement delivered through cement delivery lumen (224) to
fill the void within the intervertebral space. Bone cement
delivered through the tentacle (214) may be allowed to fully set or
only partially set prior to delivering cement through delivery
lumen (224). In one version, flowable material may delivered via
the cement delivery lumen (224) and/or the delivery tentacle (214)
prior to inflation of the balloon (212), where, for example, bone
cement may be delivered via the tentacle (214) prior to inflation
and, upon inflation, the bone cement is urged into any cracks that
may be present in cortical bone.
[0084] Step (318) further includes delivering multiple successive
layers of a material, such as bone cement, to the inner surface of
a vertebral cavity. For example, a layer of bone cement may be
delivered through the tentacle (214) and allowed to set for a
predetermined period of time. Multiple successive layers of bone
cement, therapeutic materials, fluids, or the like, may then be
provided within the vertebral cavity. One or a plurality of layers
or coatings may be delivered with the fracture reduction element
(200) and/or other delivery instruments.
[0085] The step of Deflating the Fracture Reduction Apparatus Step
(319) includes partially deflating the fracture reduction apparatus
(200) such that bone cement can be delivered into the cavity. The
balloon (212) of the fracture reduction apparatus (200) is deflated
by withdrawing the syringe associated with access port (202) to
draw fluid out of the balloon (212). Removing fluid with the
syringe decreases the volume of saline within the balloon and
creates a vacuum within the balloon that helps with retraction.
Step (319) further includes fully deflating the balloon after a
sufficient amount of bone cement has been delivered in accordance
with Step (319). Step (319) further comprises mechanically wrapping
the balloon (212).
[0086] The step of Removing the Fracture Reduction Apparatus
Through the Cannula Step (320) includes removing the fracture
reduction apparatus (200) after the balloon (212) has been
substantially deflated and the cavity has been filled with bone
cement. While the balloon (212) is mostly removed from the
vertebra, bone cement is delivered through the cement delivery
lumen (224) to fill the cavity. In this manner, the bone cement is
able to fill the cavity while the vertebra is being compressed
outwardly to cement the vertebra with the fracture reduced. The
fracture reduction apparatus (200) is then removed through the
cannula (14). The step of Removing the Cannula Step (321) includes
removing the cannula (14) from the vertebral body after the
vertebral fracture has been reduced and bone cement injected. Step
(321) includes removing the cannula (14) from the patient's body.
Step (321) may further include inserting a stopper device through
the cannula (14), prior to removal of the cannula, that prevents
bone cement or filler material from escaping from the vertebral
cavity before beginning to set. Once the material is partially set,
the stopper device and cannula (14) may be removed.
[0087] FIGS. 16-24 depict alternative versions of the end effector
(106) of the cutting instrument (100), shown in FIGS. 5-7 and 9,
utilizing a generally band-shaped cutting element. Alternative
versions described herein utilize shape-changing cutting elements
configured to form or modify cavities in either hard or soft tissue
including, for example, cancellous bone within a vertebra. The
shape-changing behavior enables the cutting instrument (100) to be
inserted into tissue through a relatively small access opening to
form a tissue cavity having a diameter larger than the diameter of
the access point. Thus, versions described herein may be
particularly useful in minimally invasive surgery, and may be used
for at least the following specific applications, among others: (1)
treatment or prevention of bone fracture, (2) joint fusion, (3)
implant fixation, (4) tissue harvesting (especially bone), (5)
removal of diseased tissue (hard or soft tissue), (6) general
tissue removal (hard or soft tissue), (7) vertebroplasty, and (8)
kyphoplasty. Tissue cavities created in accordance with versions
described herein may be of any suitable size, shape, or
configuration including a spherical cavity, a hemispherical cavity,
a linear cavity, a groove, a channel, a cavity having varying
geometries, such as an upper hemispherical chamber and a lower
linear cavity, or any other suitable cavity configuration.
Articulation of the alternative versions of the end effector (106)
may allow for numerous cavity configurations to be created along
multiple axes and/or planes.
[0088] FIG. 16 shows one version of an end effector (406) that may
used, for example, with the cutting device (100) shown in FIG. 5.
It will be appreciated that the term "end effector" can refer,
generally, to the working end of the cutting instrument or to an
identifiable component of the cutting instrument. For example, the
end effector (406) may be coupled with the insertion tube (104),
shown in FIG. 5, or may be part of a contiguous insertion tube. The
end effector (406) includes a shaft (428), a flexible cutting
element (418), a transverse member (416), such as a guide, pin, or
catch, and a transition member (432). In the illustrated version,
the shaft (428) has a longitudinal axis A-A and a generally
circular cross-section. It will be appreciated that any suitable
cross-section, such as a generally square cross-section, a
generally elliptical cross-section, or a polygon cross-section are
contemplated. In the illustrated version, the end effector (406)
includes an aperture (434), where the flexible cutting element
(418) is configured to be housed or retained at least partially
within the end effector (406).
[0089] In the illustrated version, the flexible cutting element
(418) is formed from a flexible material, such as stainless steel,
and is coupled at a first end (422) to the end effector (406) at
about the proximal end of the aperture (434). The flexible cutting
element (418) is coupled at a second end (424) to a distal face of
the transition member (432). Couplings may be laser welds or any
other suitable connection. The flexible cutting element (418) may
be coupled at or near the proximal end of the end effector (406),
where a portion of the flexible cutting element (418) may be curled
under the proximal lip of the end effector (406), as is shown with
reference to end effector (106) in FIG. 9, to form a living hinge
that diminishes the stress placed upon the flexible cutting element
(418) when deformed. The flexible cutting element (418) may be a
flexible band, a cylinder, a ribbon, a serrated element, or have
any other suitable configuration. The flexible cutting element
(418) may have a uniform cross-section or varying
cross-section.
[0090] The transition member (432) is configured to translate along
the axis A-A such that axial motion relative to the end effector
(406) may be translated to the flexible cutting element (418) to
project the flexible cutting element (418) laterally through the
aperture (434). The transition member (432) may be slidable along a
track (426) of the end effector (406) such that rotational movement
of the transition member (432) relative to the end effector (406)
is restricted. For example, referring to FIG. 18, which is a
cross-sectional view of the end effector (406) taken along line
3-3, the transition member (432) may have a wide base (436) to
prevent such rotational movement. The transition member (432) may
have any suitable shape configured to restrict rotational movement
relative to the end effector (406) while allowing axial movement
such that the flexible cutting element (418) may be deformed or
laterally extended.
[0091] Still referring to FIG. 16, the shaft (428) is distally
coupled to a proximal face of the transition member (432) and is
connected proximally to an actuator, such as those described with
reference to the cutting device (100) shown in FIGS. 5-9. The shaft
(428) is configured to actuate the transition member (432)
proximally and distally to deform the flexible cutting element
(418). A rigid or flexible shaft (428) may extend along the axis
A-A and may be fixedly coupled with the transition member (432).
Proximally, the shaft (428) may be associated with any suitable
actuator configured to provide axial movement including, for
example, actuators and actuation mechanisms described in co-pending
U.S. patent application Ser. No. 11/600,313, which is herein
incorporated by reference in its entirety. Such actuators may
include knobs, slides, T-rails, spools, gear assemblies, triggers,
manual actuation, electrical actuation, or the like.
[0092] In FIG. 16, the flexible cutting element (418) is shown in
an expanded position configured to form a cavity in, for example,
cancellous bone tissue of a vertebra. The expanded position may be
formed by distally actuating the shaft (428) with an actuator such
that the transition member (432) urges the flexible cutting element
(418) against a ramp or inclined portion (430) that may be integral
with the end effector (406). The inclined portion (430) may be
integrally formed with the end effector (406), may be an insert, or
may otherwise be suitably configured to guide the flexible cutting
element (418) laterally through the aperture (434) as axial
compression force is applied along the axis A-A. As the shaft (428)
is actuated axially in a generally distal direction, the flexible
cutting element (418) will correspondingly deform laterally through
the aperture (434). The transition member (432) may be actuated
distally until a stop (435) is abutted along the track (426).
[0093] In one version, the flexible cutting element (418) is
configured to extend from the proximal end to the distal end, or
past the distal end, of the end effector (106), where the working
length of the cutting element (418) may comprise substantially the
full length of the end effector (406). A long working length may
increase the cutting effectiveness and efficiency of the cutting
element (418). Wrapping or curling one end of the flexible cutting
element (418) around the proximal end of the end effector (406),
such as illustrated in FIG. 16, may maximize the working length of
the cutting element (418) while also providing a living hinge that
biases the cutting element (418) outward. The flexible cutting
element may also be curled around a portion of the distal end of
the end effector as shown in FIG. 23.
[0094] When extended laterally, partially or fully, the flexible
cutting element (418) may be used to form a cavity by rotating the
end effector (406). The end effector (406) may be rotated by a
second actuation member such as, for example, the rotational member
(114) of the cutting device (100) shown in FIG. 5. For example, the
transition member (432) may be configured such that rotation is
translated to the end effector (406), where rotation of the
transition member (432) via the shaft (428) correspondingly rotates
the end effector (406). In such a manner, the shaft (428) may be
used to deform the flexible cutting element (418) and to rotate the
flexible cutting element (418) to form a cavity. Rotational and
axial motion of elements of the cutting device (100) may be
provided by one or a plurality of actuators as described
herein.
[0095] Referring to FIG. 17, the flexible cutting element (418) of
the end effector (406) may be deformed to a retracted position for
insertion, for example, into a pilot hole in a vertebra, or for
removal through a minimally invasive insertion point or cannula
upon completion of a procedure as described, for example, with
reference to FIG. 15. In the retracted position, the shaft (428)
and the transition member (432) are urged in a generally proximal
direction such that the flexible cutting element (418) is withdrawn
through the aperture (434). In the illustrated version, the
flexible cutting element (418) is drawn about a catch or transverse
member (416) to achieve a substantially controlled and uniform
retraction. When retained against the transverse member (416), the
flexible cutting element (418) may be tensioned in the retracted
position until the shaft (428) is actuated distally. The transverse
member (416), in the illustrated version, is a cylindrical bar
fixed to the sides of the end effector (406) perpendicular to the
axis A-A. The transverse member (416) is configured such that the
flexible cutting element (418) is slidable thereabout. The
transverse member (416) is one version of a catch that may have any
suitable shape, where the transverse member need not be directly
perpendicular to the axis A-A. The transverse member (416),
particularly when configured as illustrated in FIG. 8, may help
prevent the cutting element (418) from buckling during actuation.
In particular, the bottom curved surface of the transverse member
may resist buckling.
[0096] Referring to FIGS. 19-20, an alternate version of an end
effector (506) is shown where the flexible cutting element (518) is
coupled directly with the shaft (528). The flexible cutting element
(518) may be deformed as described above; however, the shaft (528)
may be rotatable relative to the end effector (506). Rotation of
the end effector (506) may be achieved via the shaft (528) by
rotating the shaft (528) until the flexible cutting element abuts
the aperture (534) and further rotation of the flexible cutting
element correspondingly rotates the end effector (506). It will be
appreciated that the flexible cutting element (518) may be
contiguous with the shaft (528).
[0097] Referring to FIGS. 21-22, alternate versions of transition
elements, taken along a line similar to that of line 3-3 of FIG.
16, are shown in cross-section. It will be appreciated that
versions of the transition elements described herein may have any
suitable configuration such as a toothed cylindrical transition
element (550) guided within a corresponding keyed channel (552) of
an end effector. As shown the transition element (550) may track
within a chamber or lumen (554) separate from an adjacent chamber
or lumen (556) which may be used, for example, as a suction or
irrigation channel. Referring to FIG. 22, the transition element
may be a toothed projecting transition element (560) configured to
slide within a corresponding channel (562). Any suitable slide or
tracking configuration is contemplated. It will be appreciated that
the blade or cutting member may also be keyed or otherwise
configured to track within the end effector.
[0098] FIGS. 23-24 illustrate an alternate version of an end
effector (606) wherein proximal actuation of a transition member
(632) with a shaft (628) expands a flexible cutting element (618)
through an aperture (634) in the end effector (606). One end of the
flexible cutting element (618) may be fixed to the distal end of
the end effector (606) and the other end may be coupled with the
transition member (632). With reference to FIG. 24, distal
actuation of the transition member (632) draws the flexible cutting
element (618) into contact with a guide pin (616), or other
restrictive member, such that the flexible cutting element (618) is
retracted into the end effector (606). It will be appreciated that
any suitable configuration using a guide pin, or other guide
member, is contemplated. Altering the position of the guide pin or
member, such as towards the proximal or distal ends of the
aperture, may alter the arcuate shape of the flexible cutting
element and provide various desirable cutting shapes for medical
procedures. As has been described herein, the end effector (606)
may be articulated, actuated, and/or rotated by any suitable means
such as, for example, the cutting device (100), shown in FIG. 5, a
T-handle, or a power drill.
[0099] Version of the flexible cutting element may have a bias
toward a "remembered" shape, be configured from a material having a
thermal response, have a curvilinear shape when expanded, have a
waveform configuration when expanded, or may otherwise be suitably
configured. The memory retention aspects of a number of materials,
such as Nitinol or stainless steel, allow for a wide range of
possible configurations that are contemplated. Shape may be
determined or varied depending on the hardness, material, response
to temperature, flexibility, and/or other properties of the cutting
elements provided.
[0100] For example, a first cavity portion may be created with a
flexible cutting element having a first configuration. After
completion of the first cavity portion, the flexible cutting
element may be changed, deformed, or transitioned to a second
configuration to change or increase the size of the first cavity to
form a second cavity. It is contemplated that a user may alternate
between shapes, configurations, and directions while creating a
cavity without removing the cavitation device from the vertebral
body. Configurations from Nitinol, for example, may be
predetermined such that a user may select a predictable shape from
a selection such that the user knows precisely which shape is being
used to cut tissue. It will be appreciated that the shapes may be
discreetly selectable configurations or, in an alternate version,
may be points along a continuum that may be selected during or
prior to a procedure. Providing a plurality of selectable
configurations and/or allowing a user to adjust the configurations
of the cutting element may permit more precise cavity creation or
modification.
[0101] Versions of the flexible cutting element may be configured,
articulated, or manipulated into any suitable shape such as, for
example, an arcuate shape, a plateau shape, a curvilinear shape, a
coiled shape, a helical shape, a laterally extended shape, a convex
shape, a concave shape, a linear shape, and/or a sinusoidal or
wave-shape. The shaft portion may be integral and contiguous with
the flexible cutting element or may be a more clearly defined or
discreet actuation member coupled with the flexible cutting
element. The distal end of the flexible cutting element may be
permanently fixed to an insertion tube, such as with a laser weld,
such that the distal end remains static as the shaft is tensioned,
rotated, compressed, articulated, and/or otherwise moved to change
the flexible cutting element from a first shape to a second shape.
The shaft and/or the insertion tube may be rotated in a clockwise
and/or counterclockwise direction to form or modify a desired
cavity.
[0102] In addition to being rotatable or movable in one or a
plurality of directions, the flexible cutting elements may be
provided with one or a plurality of surface effects to create
different cutting effects. Multiple cutting edges or surface
effects may be combined in a single flexible cutting element to
affect tissue differently depending upon the direction of cut. The
term "surface effect" shall refer to any geometry, feature,
projection, texture, treatment, edging, sharpening, tapering,
material type, hardness, memory retention, heat treating, response
to heat, roughness, smoothness, sharpness, shape, and/or
configuration of one or a plurality of surfaces, faces, edges,
points, or the like, of the flexible cutting element or any other
component of a cavitation device. Any suitable surface effect is
contemplated including, but not limited to, serrations, waves,
convexities, concavities, edging, points, sharpened edges, smooth
edges, rounded edges, flat edges, hardened edges, or combinations
thereof. It is further contemplated that a first surface effect may
be provided on a first cutting surface and a second surface effect
may be provided on a second cutting surface of a flexible cutting
element such that varying the direction of rotation varies the type
of cut or tissue effect.
[0103] Any suitable cross-section of the flexible cutting element
may be provided, where altering the shape, size, and/or
configuration of the flexible element may advantageously alter the
cutting effect, the stiffness, the sharpness, and/or other
properties of the flexible cutting element. It will be appreciated
that the illustrated versions are disclosed by way of example only
and are not intended to be limiting. Varying the cross-sections of
the flexible cutting element along the length thereof may provide
advantageous tissue effects and/or may be structurally
advantageous.
[0104] Referring to FIGS. 25-26, disclosed are alternative versions
of an inflatable device, such as may be used with the fracture
reduction apparatus (200) shown in FIG. 10, for use in orthopedic
procedures directed, for example, towards restoring the anatomy of
diseased or fractured bone. Any suitable bone, such as a vertebra,
may be prepped by providing a cavity therein in accordance with
devices and methods described herein. Pre-existing cavities or
pre-formed cavities, such as natural cavities formed within bones,
may also be utilized. As has been discussed, an inflatable device,
such as a balloon, may then be inserted into the cavity. Once
introduced, the inflatable device may be unfolded and/or inflated
through the application of air, gas, fluid, a liquid matrix, bone
paste, bone cement, bone matrix, or the like, via a lumen fluidly
connected thereto. The terms "inflate" and "inflation" shall refer
to distention with fluid and/or gas, an increase in volume,
swelling, dilation, and/or expansion. The inflatable device may
then be inflated intramedullarily with one of a plurality of lumens
to apply outward pressure to the interior surface of the fractured
bone.
[0105] Thus, the versions of inflatable balloons may be
particularly useful in minimally invasive surgery and may be used
for at least the following specific applications, among others: (1)
treatment or prevention of bone fracture, (2) joint fusion, (3)
implant fixation, (4) tissue harvesting (especially bone), (5)
removal of diseased tissue (hard or soft tissue), (6) general
tissue removal (hard or soft tissue), (7) vertebroplasty, and (8)
kyphoplasty.
[0106] Referring to FIG. 25, an inflatable device (700) is shown
having a delivery lumen (712) associated therewith and a plurality
of delivery lumen, tubes, tentacles, or projections (714), where
the projections (714) are independently filled or inflated from the
inflatable device (700) via a delivery lumen (716) and are
configured to deliver flowable material, bone cement, or other
material, through pores (718), holes, slots, apertures, or the
like, therein. In one version, the pores (718) are configured to
deliver material to a predetermined location, where multiple
apertures and the location of the tentacle help deliver cement in
multiple locations at the same time along the anterior surface of
the body. In this manner flowable material can be delivered to
desirable regions, such as the anterior surface of the body, and
can be directed away from less desirable regions such as, for
example, the posterior side of the body.
[0107] The tentacles or projections (714) may be made of any
suitable material such as balloon material, semi-rigid material,
short segments of rigid material, tacky material, memory retention
material, adhesive material, rigid material, elastomeric material,
and/or any other suitable material. The tentacles or projections
(714) may be used to deliver any suitable material including the
addition of an adhesive, bone matrix, bone paste, bone cement,
synthetic paste, therapeutic agent, healing agent, structural
agent, or other suitable material, may assist or speed the healing
process, assist in fitting the balloon properly, provide a dye or
visual marker or the like to visually identify the position of the
balloon in a bone through scans or x-ray, provide structural
support, or serve any other suitable purpose. Any suitable number
of chambers for any suitable purpose are contemplated. Projections
(714), tentacles, or the like, may then be pressurized or sized via
the associated lumen (716) to a desirable pressure, size,
configuration, shape, or the like, for the delivery of a particular
material. Any suitable number of projections (714) may be used to
deliver material at any suitable location.
[0108] Tentacles or projections (714), which include tubes, rigid
tubes, semi-rigid tubes, lumens, flexible lumens, bars, spines,
protuberances, extensions, support members, combinations thereof,
or the like, may be inserted into, attached to, affixed to, coupled
with, or formed integrally with the inflatable device (700), such
as the fracture reduction apparatus (200) shown in FIG. 10, in a
linear configuration, in a non-linear configuration, in an annular
configuration, in a lateral configuration, in a longitudinal
configuration, in a wave-shaped configuration, in a random
configuration, in a non-linear configuration, in a threaded
configuration, and/or in any other suitable configuration. The
tentacles or projections (714) may be coupled with, for example,
the inner or outer surface of the inflatable member. Delivery of
materials may be independent of the inflatable device (700) or
combined with the inflatable device. The projections (714), or the
like, may project in any suitable direction or manner, such as
outwardly from the inflatable device or inwardly towards the
centroid of the balloon (700).
[0109] Additionally, the tentacles or projections (714) may be
provided with multiple chambers, cavities, lumens, tubes, or the
like configured to perform various functions. The projections may
include a porous outer surface that is connected to a delivery
lumen, where an adhesive or the like may be administered.
Individual projections may be inflatable and may, for example,
further include concentric or concatenated chambers.
[0110] Referring to FIG. 26, a plurality of tentacles or
projections (814) may be used to deliver material, such as bone
cement, via one or a plurality of corresponding delivery lumens
(816), as illustrated, in conjunction with a balloon (800). In such
a manner, different materials may be directed to different
projections. A single tentacle or projection (814) may be
associated with a single delivery lumen (816), multiple projections
(814) may be associated with a single delivery lumen (816), and/or
multiple projections (814) may be associated with multiple delivery
lumens (816). Multiple delivery lumens (816) may be connected to a
single delivery source or to a plurality of delivery sources and
may be utilized simultaneously or at different times. In an
alternative version, the tentacle may be a sheath, lumen, or tubing
that completely or substantially covers the outer surface of the
balloon (800) where, for example, the sheath may have apertures
that can be pumped out and/or forced out when the sheath is
compressed against cortical bone.
[0111] The versions presented in this disclosure are examples.
Those skilled in the art can develop modifications and variants
that do not depart from the spirit and scope of the disclosed
cavitation devices and methods. Thus, the scope of the invention
should be determined by appended claims and their legal
equivalents, rather than by the examples given.
* * * * *