U.S. patent application number 14/481827 was filed with the patent office on 2015-09-10 for post-operative bone grown stimulant introduction method.
This patent application is currently assigned to DePuy Synthes Products, LLC. The applicant listed for this patent is DePuy Synthes Products, LLC. Invention is credited to Scott Jacobs, Jeffrey Walker.
Application Number | 20150250610 14/481827 |
Document ID | / |
Family ID | 54016254 |
Filed Date | 2015-09-10 |
United States Patent
Application |
20150250610 |
Kind Code |
A1 |
Jacobs; Scott ; et
al. |
September 10, 2015 |
Post-Operative Bone Grown Stimulant Introduction Method
Abstract
A method of revising a patient having a fusion cage implanted
within a spinal column, involving percutaneously delivering a first
end of a tube to the spinal column, fluidly connecting the first
end of the tube to the fusion cage, and delivering a bone growth
agent into the fusion cage through the tube.
Inventors: |
Jacobs; Scott; (Randolph,
MA) ; Walker; Jeffrey; (Providence, RI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DePuy Synthes Products, LLC |
Raynham |
MA |
US |
|
|
Assignee: |
DePuy Synthes Products, LLC
Raynham
MA
|
Family ID: |
54016254 |
Appl. No.: |
14/481827 |
Filed: |
September 9, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61947642 |
Mar 4, 2014 |
|
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|
Current U.S.
Class: |
623/17.16 |
Current CPC
Class: |
A61F 2/4465 20130101;
A61F 2002/3068 20130101; A61F 2002/2817 20130101; A61F 2002/30843
20130101; A61F 2002/30677 20130101; A61F 2002/30789 20130101; A61F
2002/2835 20130101; A61B 2090/3966 20160201; A61F 2310/00023
20130101; A61F 2/30965 20130101; A61F 2002/30785 20130101; A61F
2002/30787 20130101; A61F 2/442 20130101; A61F 2002/30593 20130101;
A61F 2310/00359 20130101; A61F 2002/30784 20130101; A61F 2002/3069
20130101 |
International
Class: |
A61F 2/44 20060101
A61F002/44; A61M 31/00 20060101 A61M031/00; A61F 2/46 20060101
A61F002/46 |
Claims
1. A method of revising a patient having a fusion device having a
cavity implanted within a spinal column, comprising the steps of:
a) making an incision in the patient, b) delivering through the
incision a distal end of a tube to the spinal column, c) fluidly
connecting the distal end of the tube to the cavity of the fusion
device, and d) delivering a bone growth agent into the cavity of
the fusion device through the tube.
2. The method of claim 1 further comprising, betweens steps c) and
d), the step of e) removing tissue from the cavity of the fusion
device.
3. The method of claim 2 wherein tissue removal is accomplished
with lavage.
4. The method of claim 1 wherein, in step c), the tube connects to
a port on the fusion device.
5. The method of claim 4 wherein the port is associated with a
radiographic marker.
6. The method of claim 1 further comprising, before step d), the
step of: e) fluidly connecting a bone growth transfer apparatus
containing a bone growth agent to a proximal end of the tube.
7. The method of claim 1 further comprising, before step a), the
step of: e) radiographically locating the fusion device within the
patient.
8. The method of claim 7 wherein step e) includes radiographically
aligning a pair of radiopaque rings located in the fusion
device.
9. The method of claim 1 further comprising the step of: e)
altering a component of the fusion device.
10. The method of claim 9 wherein the alteration is carried out by
a step selected from the group consisting of exchanging the
component, manipulating the component, adjusting the component,
adding a component, and removing a component.
11. The method of claim 1 further comprising the step of: e)
delivering additional bone growth agent to a location outside of
the fusion device.
12. The method of claim 11 wherein the additional bone growth agent
is delivered adjacent a facet joint.
13. The method of claim 1 wherein the bone growth agent travels
through the tube by fluid convection.
14. The method of claim 1 wherein the bone growth agent travels
through the tube in a solid carrier.
15. The method of claim 14 wherein the solid carrier snaps into the
fusion device.
16. The method of claim 14 wherein the solid carrier threads into
the fusion device.
17. The method of claim 14 wherein the solid carrier is empty
during its delivery to the implanted fusion device.
18. The method of claim 14 wherein the solid carrier is filled with
a collagen sponge during delivery to the fusion device.
19. The method of claim 14 wherein the carrier is filled with a
scaffold material during delivery to the fusion device.
20. The method of claim 1 wherein the bone growth agent is
flowable.
21. A method of revising a patient having a fusion device implanted
within a disc space, comprising the steps of: a) making an incision
in the patient, b) percutaneously delivering through the incision a
first end of a tube to the disc space, c) fluidly connecting the
first end of the tube to the fusion device, d) passing an
instrument down the tube, and e) manipulating the instrument to
alter a component of the fusion cage.
22. The method of claim 21 wherein the manipulation results in an
alteration selected from the group consisting of exchanging the
component, manipulating the component, adjusting the component,
adding a component, and removing a component of the fusion
device.
23. The method of claim 21 wherein the manipulations results in
removing a pin or screw to allow motion in a previously-locked
device, or to increase the motion in a constrained-motion
device.
24. An assembly comprising: a) an intervertebral fusion device
having a cavity and a port; b) a tube having a proximal end and a
distal end; c) a bone growth transfer apparatus containing a bone
growth agent; wherein the proximal end of the tube is fluidly
connected to the bone growth transfer apparatus; and wherein the
distal end of the tube is fluidly connected to the port of the
fusion device.
25. The device of claim 24 wherein the bone growth agent is a
non-autologous bone growth agent.
26. The device of claim 24 wherein the bone growth agent is a
synthetic bone growth agent.
27. The device of claim 24 wherein the port is surrounded by a
radiographic ring.
28. The device of claim 24 wherein the bone growth transfer
apparatus is a syringe.
29. The device of claim 24 wherein the tube is sized to extend from
the skin of a patient to a disc space in the patient.
30. An intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, and a vertical
throughhole, the cage further comprising a pair of radiopaque rings
respectively embedded in two of the different walls, wherein the
rings align.
31. An intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, a vertical
throughhole, a docking port, and a radiopaque marker indicating the
docking port.
32. The cage of claim 31 wherein the radiopaque marker is a ring
that surrounds the docking port.
33. The cage of claim 31 wherein the docking port is in fluid
communication with the vertical throughhole.
34. An intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, a vertical
throughhole, and a plurality of docking ports adapted to receive a
tube.
35. The cage of claim 34 wherein each docking port is in fluid
communication with the vertical throughhole.
36. The cage of claim 34 wherein at least one of the docking ports
is located in a sidewall.
37. The cage of claim 34 having a distal end of a tube received in
one of the docking ports.
38. The cage of claim 37 having a bone growth transfer apparatus
containing a bone growth agent fluidly connected to a proximal end
of the tube.
39. An assembly comprising: a) an intervertebral fusion device
having a cavity and a port; b) a tube having a proximal end and a
distal end; c) a disc-manipulating instrument received in the tube,
wherein the distal end of the tube is fluidly connected to the port
of the fusion device, wherein the disc-manipulating instrument has
a distal working end located in the cavity of the fusion
device.
40. The device of claim 39 wherein the disc-manipulating instrument
is adapted to remove non-bony tissue from the cavity of the fusion
device.
41. The device of claim 39 wherein the disc-manipulating instrument
is adapted to cut a vertebral endplate.
42. The device of claim 39 wherein the disc-manipulating instrument
is a drill.
43. The device of claim 39 wherein the disc-manipulating instrument
is a rasp.
44. The device of claim 39 wherein the disc-manipulating instrument
is a loop cutter.
45. An assembly comprising: a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; b) a tube having a proximal end and a distal end; c)
a preformed solid bone growth agent located in the tube; wherein
the distal end of the tube is fluidly connected to the port of the
fusion device.
46. The assembly of claim 45 wherein the preformed solid bone
growth agent has a cylindrical shape.
47. The assembly of claim 45 wherein the preformed solid bone
growth agent has a length substantially equal to a length of the
cavity of the fusion device.
48. An assembly comprising: a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; b) a tube having a proximal end and a distal end; c)
a solid carrier having a bone growth agent therein; wherein the
distal end of the tube is fluidly connected to the port of the
fusion device, and wherein the solid carrier is located in the
tube.
49. The assembly of claim 48 wherein the solid carrier snaps into
the fusion cage.
50. The assembly of claim 48 wherein the solid carrier threads into
the fusion cage.
51. An assembly comprising: a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; b) a solid carrier having a bone growth agent
therein; wherein the solid carrier is located in the cavity of the
fusion device.
52. The assembly of claim 51 wherein the solid carrier snaps into
the fusion cage.
53. The assembly of claim 51 wherein the solid carrier threads into
the fusion cage.
54. A method of revising a patient having a fusion device having a
cavity implanted adjacent a bone, comprising the steps of: a)
making an incision in the patient, b) delivering through the
incision a distal end of a tube to the bone, c) fluidly connecting
the distal end of the tube to the cavity of the fusion device, and
d) delivering a bone growth agent into the cavity of the fusion
device through the tube.
Description
CONTINUING DATA
[0001] This patent application claims priority from co-pending U.S.
provisional patent application U.S. Ser. No. 61/947,642, filed Mar.
4, 2014, entitled "Post-Operative Bone Growth Stimulant
Introduction Method", Jacobs et al., (Docket No. DSP5062USPSP), the
specification of which is incorporated by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] The natural intervertebral disc contains a jelly-like
nucleus pulposus surrounded by a fibrous annulus fibrosus. Under an
axial load, the nucleus pulposus compresses and radially transfers
that load to the annulus fibrosus. The laminated nature of the
annulus fibrosus provides it with a high tensile strength and so
allows it to expand radially in response to this transferred
load.
[0003] In a healthy intervertebral disc, cells within the nucleus
pulposus produce an extracellular matrix (ECM) containing a high
percentage of proteoglycans. These proteoglycans contain sulfated
functional groups that retain water, thereby providing the nucleus
pulposus within its cushioning qualities. These nucleus pulposus
cells may also secrete small amounts of cytokines such as
interleukin-1.beta. and TNF-.alpha. as well as matrix
metalloproteinases ("MMPs"). These cytokines and MMPs help regulate
the metabolism of the nucleus pulposus cells.
[0004] In some instances of disc degeneration disease (DDD),
gradual degeneration of the intervetebral disc is caused by
mechanical instabilities in other portions of the spine. In these
instances, increased loads and pressures on the nucleus pulposus
cause the cells within the disc (or invading macrophases) to emit
larger than normal amounts of the above-mentioned cytokines In
other instances of DDD, genetic factors or apoptosis can also cause
the cells within the nucleus pulposus to emit toxic amounts of
these cytokines and MMPs. In some instances, the pumping action of
the disc may malfunction (due to, for example, a decrease in the
proteoglycan concentration within the nucleus pulposus), thereby
retarding the flow of nutrients into the disc as well as the flow
of waste products out of the disc. This reduced capacity to
eliminate waste may result in the accumulation of high levels of
toxins that may cause nerve irritation and pain.
[0005] As DDD progresses, toxic levels of the cytokines and MMPs
present in the nucleus pulposus begin to degrade the extracellular
matrix, in particular, the MMPs (as mediated by the cytokines)
begin cleaving the water-retaining portions of the proteoglycans,
thereby reducing its water-retaining capabilities. This degradation
leads to a less flexible nucleus pulposus, and so changes the
loading pattern within the disc, thereby possibly causing
delamination of the annulus fibrosus. These changes cause more
mechanical instability, thereby causing the cells to emit even more
cytokines, thereby upregulating MMPs. As this destructive cascade
continues and DDD further progresses, the disc begins to bulge ("a
herniated disc"), and then ultimately ruptures, causing the nucleus
pulposus to contact the spinal cord and produce pain.
[0006] One proposed method of managing these problems is to remove
the problematic disc and replace it with a porous device that
restores disc height and allows for bone growth therethrough for
the fusion of the adjacent vertebrae. These devices are commonly
called "fusion devices". The goal of a fusion device is to
stabilize the motion segment associated with the problematic disc
space so that a fusion can occur between the adjacent vertebrae.
The conventional fusion device is typically a hollow cage that
contains graft material that assists in the formation of new bone.
The fusion device provides a bloody pathway between the endplates
of the adjacent vertebrae for new bone to form.
[0007] Some fusion devices provide for stabilization of the
functional spinal unit (FSU) in three phases. In the initial phase,
the device is fixed to the FSU, typically via screws that pass
through the fusion device and into the neighboring bone. In the
second phase, bone grows into the device. In the third phase, bone
grows through the device.
[0008] Although spinal fusion has met with significant success,
there are times when the surgeon may decide to revise a patient due
to symptomatic or asymptomatic non-union or fractured fusion. For
example, although the anticipated fusion of the disc space
generally occurs, there are times when the fusion is incomplete.
For example, it has been reported that in one series 16% of the
cases had intercalary pseudoarthrosis, which is visible bone
ingrowth with a visible void between the bones. (Yue, ISASS, 2012).
The current treatments for these situations include waiting
additional time for the fusion to become complete, providing
additional posterior fixation, or revising the fusion device. In
such cases, a revision surgery is typically required in which the
patient is re-opened and the cage removed. These revisions are
expensive and pose significant safety risks to the patient.
[0009] Therefore, there is a need in cases of incomplete fusion for
a suitable revision alternative to cage removal.
[0010] US 2011-0137418 (O'Neil) discloses a fusion cage having a
suction tube attached thereto at a port. See FIGS. 3B and 10C.
[0011] US 2008-0154377 (Voellmicke) discloses the insertion of a
fusion cage into the disc space, followed by filling the empty cage
with flowable bone graft by introducing the bone graft through an
annulus in the cage.
[0012] The HEALOS FX.TM. surgical technique discloses injecting a
bone growth agent from a syringe through a cannula to an
implantation site in a disc space. See FIG. 14.
SUMMARY OF THE INVENTION
[0013] The present invention relates to a novel method of revision
that delivers a bone growth agent to the implanted cage.
Preferably, a tube is percutaneously delivered to the cage site and
docked to the cage, any tissue that has grown into the cage is
removed through the tube, and bone growth agent is then delivered
through the tube to the cage. This method eliminates the need for
cage removal, thereby reducing the risk and cost associated with
the revision.
[0014] Therefore, in accordance with the present invention, there
is provided a method of revising a patient having a fusion device
having a cavity implanted within a spinal column, comprising the
steps of: [0015] a) making an incision in the patient, [0016] b)
delivering through the incision a distal end of a tube to the
spinal column, [0017] c) fluidly connecting the distal end of the
tube to the cavity of the fusion device, and [0018] d) delivering a
bone growth agent into the cavity of the fusion device through the
tube.
[0019] Also in accordance with the present invention, there is
provided a method of revising a patient having a fusion device
implanted within a disc space, comprising the steps of: [0020] a)
making an incision in the patient, [0021] b) percutaneously
delivering through the incision a first end of a tube to the disc
space, [0022] c) fluidly connecting the first end of the tube to
the fusion device, [0023] d) passing an instrument down the tube,
and [0024] e) manipulating the instrument to alter a component of
the fusion cage.
[0025] Also in accordance with the present invention, there is
provided an assembly comprising: [0026] a) an intervertebral fusion
device having a cavity and a port; [0027] b) a tube having a
proximal end and a distal end; [0028] c) a bone growth transfer
apparatus containing a bone growth agent; wherein the proximal end
of the tube is fluidly connected to the bone growth transfer
apparatus; and wherein the distal end of the tube is fluidly
connected to the port of the fusion device.
[0029] Also in accordance with the present invention, there is
provided an intervertebral fusion cage having an anterior wall and
a posterior wall connected by a pair of side walls, and a vertical
throughhole, the cage further comprising a pair of radiopaque rings
respectively embedded in two of the different walls, wherein the
rings align.
[0030] Also in accordance with the present invention, there is
provided an intervertebral fusion cage having an anterior wall and
a posterior wall connected by a pair of side walls, a vertical
throughhole, a docking port, and a radiopaque marker indicating the
docking port.
[0031] Also in accordance with the present invention, there is
provided an intervertebral fusion cage having an anterior wall and
a posterior wall connected by a pair of side walls, a vertical
throughhole, a docking port, and a radiopaque marker indicating the
docking port.
[0032] Also in accordance with the present invention, there is
provided an assembly comprising: [0033] a) an intervertebral fusion
device having a cavity and a port; [0034] b) a tube having a
proximal end and a distal end; [0035] c) a disc-manipulating
instrument received in the tube, wherein the distal end of the tube
is fluidly connected to the port of the fusion device, wherein the
disc-manipulating instrument has a distal working end located in
the cavity of the fusion device.
[0036] Also in accordance with the present invention, there is
provided an assembly comprising: [0037] a) an intervertebral fusion
device having a cavity and a port, wherein the port is fluidly
connected to the cavity; [0038] b) a tube having a proximal end and
a distal end; [0039] c) a preformed solid bone growth agent located
in the tube; wherein the distal end of the tube is fluidly
connected to the port of the fusion device.
[0040] Also in accordance with the present invention, there is
provided an assembly comprising: [0041] a) an intervertebral fusion
device having a cavity and a port, wherein the port is fluidly
connected to the cavity; [0042] b) a tube having a proximal end and
a distal end; [0043] c) a solid carrier having a bone growth agent
therein; wherein the distal end of the tube is fluidly connected to
the port of the fusion device, and wherein the solid carrier is
located in the tube.
[0044] Also in accordance with the present invention, there is
provided an assembly comprising: [0045] a) an intervertebral fusion
device having a cavity and a port, wherein the port is fluidly
connected to the cavity; [0046] b) a solid carrier having a bone
growth agent therein; wherein the solid carrier is located in the
cavity of the fusion device.
[0047] Also in accordance with the present invention, there is
provided a method of revising a patient having a fusion device
having a cavity implanted adjacent a bone, comprising the steps of:
[0048] a) making an incision in the patient, [0049] b) delivering
through the incision a distal end of a tube to the bone, [0050] c)
fluidly connecting the distal end of the tube to the cavity of the
fusion device, and [0051] d) delivering a bone growth agent into
the cavity of the fusion device through the tube.
DESCRIPTION OF THE FIGURES
[0052] FIG. 1A discloses a conventional cage implanted in a disc
space.
[0053] FIGS. 1B-1C disclose a fusion cage having radiopaque
rings.
[0054] FIGS. 2A-2B disclose a tube approach and docking to an
implanted fusion device.
[0055] FIG. 3 discloses an implanted cage with tissue removed.
[0056] FIG. 4 discloses the delivery of the bone growth agent to
the fusion device.
[0057] FIG. 5 discloses removal of the tube from the port on the
fusion device.
[0058] FIG. 6 discloses a revised cage of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0059] In some preferred embodiments, there is provided a method of
revising a patient having a fusion device having a cavity implanted
within a disc space, comprising the steps of: [0060] a) making an
incision in the patient, [0061] b) delivering through the incision
a distal end of a tube to the disc space, [0062] c) fluidly
connecting the distal end of the tube to the cavity of the fusion
device, and [0063] d) delivering a bone growth agent into the
cavity of the fusion device through the tube.
[0064] In some embodiments, a pusher is used to push the bone
growth agent through a tube into the cavity.
[0065] In some preferred embodiments, the method of revising a
patient having a fusion cage having a cavity, wherein the cage is
implanted within a disc space, comprises the steps of: [0066] a)
making an incision in the patient, [0067] b) percutaneously
delivering through the incision a distal end of a tube to the disc
space, [0068] c) fluidly connecting the distal end of the tube to
the fusion cage, [0069] d) using lavage to remove non-bony tissue
from the cavity of the fusion cage, [0070] e) fluidly connecting
the proximal end of the tube to a bone growth agent transfer
apparatus; and [0071] f) delivering a bone growth agent from the
bone growth agent transfer apparatus into the cavity of the fusion
cage through the tube.
[0072] Before surgically undertaking revision of the cage, it is
necessary to first locate the cage in the patient. If the revision
procedure is to be carried out percutaneously (so that a direct
line-of-sight to the cage is unavailable), then the surgeon must
first radiographically locate the fusion cage within the patient.
This can be accomplished by using radiology to align a pair of
radiopaque rings located in the fusion cage. When the rings are
aligned, the surgeon knows the orientation of the cage relative to
the perspective of the imaging device.
[0073] Next, preferably, the tube is delivered to the fusion cage
in a percutaneous manner, thereby minimizing the invasiveness of
the procedure. In other embodiments, however, the tube may be
delivered through an open procedure.
[0074] The tube can have a radiographic marker (such as a ring)
placed at its distal end in order to track the tube
radiographically as it travels from the patient's skin to the
fusion cage. This radiographic tracking of the tube guarantees that
the tube will always move towards the cage. Once the distal end of
the tube reaches the cage, it can dock onto a port provided on the
cage. This port provides a fluid connection between the tube and
the internal cavity of the cage. Likewise, the port of the cage can
be surrounded by a radiographic marker ring, so that the surgeon
can easily direct the distal end of the tube towards the port to
which it will dock.
[0075] Before delivering the bone growth agent to the cage, it is
useful to remove any non-bony tissue that has grown into the cage
from the surrounding vertebrae because it is the intent of the
revision of the present invention to replace this non-bony tissue
with bony tissue. In these cases, the percutaneous tube can be used
as an access port through which a combination fluid jet-aspirator
is delivered to the disc space. The fluid jet creates a lavage of
the site and cuts non-bony tissue within the cage, while the
aspirator removes the cut tissue from the cage. Typically, the
fluid used for the lavage is saline. In some embodiments, the
tissue removed from the device is non-bony tissue. In others, the
tissue removed from the device includes both non-bony and bony
tissue.
[0076] Once the tissue is cleared, the combination fluid
jet-aspirator is removed from the tube and the proximal end of the
tube is fluidly connected to a bone growth transfer apparatus. In
some embodiments, this apparatus may be a simple syringe loaded
with bone paste. Typically, the connection of the bone growth
transfer apparatus and the proximal end of the tube is accomplished
via mating Luer-locks situated on the proximal end of the tube and
the distal end of the bone growth transfer apparatus.
[0077] Next, the bone growth agent is delivered from the bone
growth transfer apparatus to the cavity within the fusion cage by
actuating the bone growth transfer apparatus. When a syringe is
used as the bone growth transfer apparatus and so stores the bone
growth agent, this may be accomplished by simply depressing the
plunger on the syringe. The delivery of the bone growth agent
should be carried out until the cavity within the cage is filled
with bone growth agent.
[0078] In some embodiments, after the bone growth agent is
delivered to the cage but before the tube is removed, a plug may be
inserted into the port in order to prevent the bone growth agent
from leaking out the opening of the port. Alternatively, the plug
may be replaced with a self-sealing membrane. In some embodiments,
the plug/membrane can be inserted with the fusion device in the
original procedure. In other embodiments, the plug/membrane can be
inserted into the fusion device during the revision.
[0079] Once the cage is re-filled with a bone growth agent, the
tube is removed from the cage and the patient is closed.
[0080] Although delivering a flowable bone growth agent to the
implanted cage is a preferred embodiment of the present invention,
it is anticipated that there are other ways of revising the cage.
In some embodiments, the revision may be simply altering a
component of the fusion cage. This alteration may be carried out by
a step selected from the group consisting of exchanging the
component, manipulating the component, adjusting the component,
adding a component, and removing a component of the fusion device.
By way of example, in one embodiment, a pin or screw may be removed
to allow motion in a previously-locked device, or to increase the
motion in a constrained-motion device.
[0081] It is also contemplated by the present invention to
approach, prepare, place and/or retain additional bone growth agent
outside or partially inside the device. In some embodiments
thereof, additional bone growth agent may also be delivered to
locations outside of the fusion cage. This step would seek to
stabilize the spine in areas other than the disc space of concern.
In some embodiments thereof, the additional bone growth agent is
delivered adjacent a facet joint of the FSU of concern. For
example, there may be placement and retention of a bone marrow
aspirate-soaked ChronOS.TM. strip to the facet area of the desired
level via a percutaneous posterior approach.
[0082] In preferred embodiments, the bone growth agent is provided
in a flowable form and travels through the tube by fluid
convection. However, in other embodiments, the bone growth agent
may travel through the tube in a solid carrier that is pushed
through the tube. In some embodiments thereof, this solid carrier
can snap into the fusion cage, while in others this solid carrier
threads into the fusion cage. The solid carrier may be delivered to
the implanted fusion cage as an empty carrier that is then filled
with bone growth agent by the surgeon. Alternatively, the solid
carrier may be delivered to the implanted fusion cage filled with a
collagen sponge, with additional fluid bone growth agent to be
added by the surgeon. The solid carrier may further be delivered to
the implanted fusion cage filled with a scaffold material, with
additional fluid bone growth agent to be added by the surgeon. In
some embodiments, a plug/cap with a diaphragm is provided in order
to facilitate injection of these fluids.
[0083] In some embodiments, the tube approaches the implanted
fusion cage along the same pathway used to originally implant the
fusion cage. In others, the tube approaches the implanted fusion
cage from a pathway different than that used to originally implant
the fusion cage. The approach taken by the tube to the implanted
cage can include but is not limited to an anterior approach, a
lateral approach, a far lateral approach, a posterior approach or
an axial (L5-S1) approach.
[0084] Now referring to FIGS. 1a-1c, the surgeon locates the fusion
device 1 within the patient with radiographic imaging by aligning
the radiopaque rings 3 of the device. Now referring to FIGS. 2a-2b,
the tube 5 approaches the fusion device and docks to the fusion
device. Now referring to FIG. 3, the physician opens a canal in the
fusion device by removing non-bony tissue with the fusion device.
Now referring to FIG. 4, the physician inserts bone growth agent 9
into the cavity of the fusion device by actuating syringe 11, which
is attached to the proximal end 10 of the tube. Now referring to
FIG. 5, the distal end 15 of the tube is then removed from the port
13 of the fusion cage. Lastly, the physician radiographically
verifies placement of the revised device. FIG. 6 shows a revised
cage of the present invention having a cylindrically-shaped
preformed bone growth agent therein.
[0085] In some embodiments of the present invention, there is
provided an assembly comprising: [0086] a) an intervertebral fusion
device having a cavity and a port; [0087] b) a tube having a
proximal end and a distal end; [0088] c) a bone growth transfer
apparatus containing a bone growth agent; wherein the proximal end
of the tube is fluidly connected to the bone growth transfer
apparatus; and wherein the distal end of the tube is fluidly
connected to the port of the fusion device.
[0089] In some embodiments, the bone growth agent is a
non-autologous bone growth agent, while in others the bone growth
agent is a synthetic bone growth agent.
[0090] In some embodiments, the port is surrounded by a
radiographic ring.
[0091] In some embodiments, the tube is sized to extend from the
skin of a patient to a disc space in the patient.
[0092] In accordance with the present invention, there is provided
an intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, and a vertical
throughhole, the cage further comprising a pair of radiopaque rings
respectively embedded in two of the different walls, wherein the
rings align.
[0093] In accordance with the present invention, there is provided
an intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, a vertical
throughhole, a docking port, and a radiopaque marker indicating the
docking port.
[0094] Preferably, the radiopaque marker is a ring that surrounds
the docking port, and the docking port is in fluid communication
with the vertical throughhole.
[0095] In accordance with the present invention, there is provided
an intervertebral fusion cage having an anterior wall and a
posterior wall connected by a pair of side walls, a vertical
throughhole, and a plurality of docking ports adapted to receive a
tube.
[0096] Preferably, each docking port is in fluid communication with
the vertical throughhole, and at least one of the docking ports is
located in a sidewall.
[0097] In some embodiments, the cage has a distal end of a tube
received in one of the docking ports, and has a bone growth
transfer apparatus containing a bone growth agent fluidly connected
to a proximal end of the tube.
[0098] In accordance with the present invention, there is provided
an assembly comprising: [0099] a) an intervertebral fusion device
having a cavity and a port; [0100] b) a tube having a proximal end
and a distal end; [0101] c) a disc-manipulating instrument received
in the tube, wherein the distal end of the tube is fluidly
connected to the port of the fusion device, wherein the
disc-manipulating instrument has a distal working end located in
the cavity of the fusion device.
[0102] In some embodiments, the disc-manipulating instrument is
adapted to remove non-bony tissue from the cavity of the fusion
device, or is adapted to cut a vertebral endplate.
[0103] Preferably, the disc-manipulating instrument is either a
drill, a rasp, or a loop cutter.
[0104] In some embodiments, the tube, drill and pusher are
assembled outside the patient. For example, the tube, drill and
pusher are assembled at the manufacturing facility. In other
embodiments, the tube, drill and pusher are inserted piece-by-piece
in the patient.
[0105] In accordance with the present invention, there is provided
an assembly comprising: [0106] a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; [0107] b) a tube having a proximal end and a distal
end; [0108] c) a preformed solid bone growth agent located in the
tube; wherein the distal end of the tube is fluidly connected to
the port of the fusion device. [0109] Preferably, the preformed
solid bone growth agent has a cylindrical shape, and has a length
substantially equal to a length of the cavity of the fusion
device.
[0110] In accordance with the present invention, there is provided
an assembly comprising: [0111] a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; [0112] b) a tube having a proximal end and a distal
end; [0113] c) a solid carrier having a bone growth agent therein;
wherein the distal end of the tube is fluidly connected to the port
of the fusion device, and wherein the solid carrier is located in
the tube.
[0114] In some embodiments, the solid carrier snaps into or threads
into the fusion cage.
[0115] In accordance with the present invention, there is provided
an assembly comprising: [0116] a) an intervertebral fusion device
having a cavity and a port, wherein the port is fluidly connected
to the cavity; [0117] b) a solid carrier having a bone growth agent
therein; wherein the solid carrier is located in the cavity of the
fusion device.
[0118] Preferably, the solid carrier snaps into the fusion cage, or
threads into the fusion cage.
[0119] The method of the present invention supports the principles
of sound spinal surgery management. It supports anatomic reduction
because the anatomic relationships remain unchanged from the
initial procedure. It supports stable fixation by docking directly
to a dedicated feature (port) on the implant, so that previously
placed hardware is not disturbed. It supports preservation of the
blood supply, as creation of the canal (via tissue removal) for the
bone growth agent removes non-bony tissue and may cause bleeding
only in the area of the desired bone growth. Lastly, it supports
early mobilization, as the small incision and minimal tissue
reduction allow patients to return home on the same day as the
revision with only minor post-operative discomfort.
[0120] Complimentary technologies may also be used to assist the
revision surgery of the present invention. In some embodiments,
image guided surgery equipment and instruments may be used to plan
the incision, guide the tube to the implanted fusion device, and
guide instruments through tissue dissection. Intraoperative
neuromonitoring may be used to guide the approach of the tube to
the fusion device, particularly when taking a lateral approach. In
some embodiments, the probe and dilator from ORACLE.TM., available
from DePuy Synthes Spine of Raynham, Mass., USA. may be used. In
some embodiments, the SPOTLIGHT.TM. retractor available from DePuy
Synthes Spine of Raynham, Mass., USA. may be used.
[0121] It is anticipated that the method of the present invention
can be carried out upon a conventional intervertebral fusion cage.
These include PLIF cages, TLIF cages, ALIF cages and lateral
cages.
[0122] The intervertebral fusion cage of the present invention may
be manufactured from any biocompatible flexible material suitable
for use in interbody fusion procedures. In some embodiments, the
cage comprises a composite comprising 40-99% polyarylethyl ketone
PAEK, and optionally 1-60% carbon fiber. Such a cage is
radiolucent. Preferably, the polyarylethyl ketone PAEK is selected
from the group consisting of polyetherether ketone PEEK, polyether
ketone ketone PEKK, polyether ketone ether ketone ketone PEKEKK,
and polyether ketone PEK. Preferably, cage is made from woven, long
carbon fiber laminates. Preferably, the PAEK and carbon fiber are
homogeneously mixed. In some embodiments, the composite consists
essentially of PAEK and carbon fiber. In some embodiments, the
composite comprises 60-80 wt % PAEK and 20-40 wt % carbon fiber,
more preferably 65-75 wt % PAEK and 25-35 wt % carbon fiber. In
some embodiments, the cage is made from materials used in carbon
fibers cages marketed by DePuy Synthes Spine, Raynham, Mass., USA.
In some embodiments, the composite is PEEK-OPTIMA.TM., available
from Invibio of Greenville, N.C.
[0123] In other embodiments, the cage is made from a flexible metal
such as a titanium alloy such as nitinol.
[0124] In other embodiments, the cage is made from structural
allograft or xenograft.
[0125] In preferred embodiments, the cage is provided in a sterile
form.
[0126] In some embodiments, the bone growth agent may be HEALOS
FX.TM., a flowable collagen-based material available from DePuy
Synthes Spine of Raynham, Mass., USA. In other embodiments, the
bone growth agent may be ChronOS.TM., a tricalcium phosphate
material available from DePuy Synthes Spine of Raynham, Mass., USA.
In other embodiments, the bone growth agent may be a CONFORM.TM.
cube or cylinder, a demineralized bone material available from
DePuy Synthes Spine of Raynham, Mass., USA. In other embodiments,
the bone growth agent may be DBX.TM., a demineralized bone matrix
material available from DePuy Synthes Spine of Raynham, Mass.,
USA.
[0127] In some embodiments, a PMMA bone cement is injected into the
fusion device. In preferred embodiments, this PMMA bone cement is
the CONFIDENCE.TM. bone cement, available from DePuy Synthes Spine
of Raynham, Mass., USA, and it is injected with the CONFIDENCE.TM.
cement injection system, available from DePuy Synthes Spine of
Raynham, Mass., USA,
[0128] In some embodiments, the bone forming agent is a growth
factor. As used herein, the term "growth factor" encompasses any
cellular product that modulates the growth or differentiation of
other cells, particularly connective tissue progenitor cells. The
growth factors that may be used in accordance with the present
invention include, but are not limited to, members of the
fibroblast growth factor family, including acidic and basic
fibroblast growth factor (FGF-1 and FGF-2) and FGF-4; members of
the platelet-derived growth factor (PDGF) family, including
PDGF-AB, PDGF-BB and PDGF-AA; EGFs; VEGF; members of the
insulin-like growth factor (IGF) family, including IGF-I and -II;
the TGF-.beta. superfamily, including: TGF-.beta.1, 2 and 3;
osteoid-inducing factor (OIF), angiogenin(s); endothelins;
hepatocyte growth factor and keratinocyte growth factor; members of
the bone morphogenetic proteins (BMPs) BMP-1, BMP-3 BMP-2, OP-1,
BMP-2A, BMP-2B, BMP-7 and BMP-14, including HBGF-1 and HBGF-2;
growth differentiation factors (GDFs), members of the hedgehog
family of proteins, including indian, sonic and desert hedgehog;
ADMP-1; bone-forming members of the interleukin (IL) family;
rhGDF-5; and members of the colony-stimulating factor (CSF) family,
including CSF-1, G-CSF, and GM-CSF; and isoforms thereof.
[0129] In some embodiments, these growth factors can be supplied
through an implantable pump that is docked to the cage during the
primary or revision surgery.
[0130] In some embodiments, platelet concentrate is provided as the
bone forming agent. In one embodiment, the growth factors released
by the platelets are present in au amount at least two-fold (e.g.,
four-fold) greater than the amount found in the blood from which
the platelets were taken. In some embodiments, the platelet
concentrate is autologous. In some embodiments, the platelet
concentrate is platelet rich plasma (PRP). PRP is advantageous
because it contains growth factors that can restimulate the growth
of the bone, and because its fibrin matrix provides a suitable
scaffold for new tissue growth.
[0131] In some embodiments, the bone forming agent comprises an
effective amount of a bone morphogenic protein (BMP). BMPs
beneficially increasing bone formation by promoting the
differentiation of mesenchymal stem cells (MSCs) into osteoblasts
and their proliferation.
[0132] In some embodiments, between about 1 ng and about 10 mg of
BMP are administered into the target disc space. In sonic
embodiments, between about 1 microgram (.mu.g) and about 1 mg of
BMP are administered into the target disc space.
[0133] In many preferred embodiments, the bone forming agent is a
porous matrix, and is preferably injectable.
[0134] The porous matrix of the present invention may contain
porous or semi-porous collagen, extracellular matrices, metals
(such as Ti, Ti64, CoCr, and stainless steel), polymers (such as
PEEK, polyethylene, polypropylene, and PET) resorbable polymers
(such as PTA, PDA, PEO, PEG, PVA, and capralactides), bone
substitutes (such as TCP, HA, and CaP), autograft, allograft (such
as allograft beads), xenograft, and/or blends thereof. Matrices may
be orientated to enable flow from bony attachment locations to the
aspiration port. Matrices may be layered with varying densities,
pore structures, materials to enable increase stem filter at
desired locations via density, pore size, affinity, as well as
fluid flow control (laminar, turbilant, and/or tortuous path).
[0135] In some embodiments, the porous matrix is a mineral. In one
embodiment, this mineral comprises calcium and phosphorus. In some
embodiments, the mineral is selected from the group consisting of
calcium phosphate, tricalcium phosphate and hydroxyapatite. In one
embodiment, the average porosity of the matrix is between about 20
and about 500 .mu.m, for example, between about 50 and about 250
.mu.m. In yet other embodiments of the present invention, in situ
porosity is produced in the injected matrix to produce a porous
scaffold in the interbody space. Once the in situ porosity is
produced in the space, the surgeon can inject other therapeutic
compounds into the porosity, thereby treating the surrounding
tissues and enhancing the remodeling process of the target
tissue.
[0136] In some embodiments, the mineral is administered in a
granule form. It is believed that the administration of granular
minerals promotes the formation of the hone growth around the
minerals such that osteointegration occurs.
[0137] In some embodiments, the mineral is administered in a
settable-paste form. In this condition, the paste sets up in vivo,
and thereby immediately imparts post-treatment mechanical support
to the interbody space.
[0138] In another embodiment, the treatment is delivered via
injectable absorbable or non-absorbable cement to the target space.
The treatment is formulated using bioabsorbable macro-sphere
technologies, such that it will allow the release of the bone
forming agent. The cement gill provide the initial stability
required to treat pain in target tissues. These tissues include,
but are not limited to, hips, knee, vertebral body and iliac crest.
In some embodiments, the cement is selected from the group
consisting of calcium phosphate, tricalcium phosphate and
hydroxyapatite. In other embodiments, the cement is any hard
biocompatible cement, including PMMA, processed autogenous and
allograft bone. Hydroxylapatite is a preferred cement because of
its strength and biological profile. Tricalcium phosphate may also
be used alone or in combination with hydroxylapatite, particularly
if some degree of resorption is desired in the cement.
[0139] In some embodiments, the porous matrix comprises a
resorbable polymeric material.
[0140] In some embodiments, the bone forming agent comprises an
injectable precursor fluid that produces the in situ formation of a
mineralized collagen composite. In some embodiments, the injectable
precursor fluid comprises: [0141] a) a first formulation comprising
an acid-soluble type I collagen solution (preferably between about
1 mg/ml and about 7 mg/ml collagen) and [0142] b) a second
formulation comprising liposomes containing calcium and
phosphate.
[0143] Combining the acid-soluble collagen solution with the
calcium- and phosphate-loaded liposomes results in a
liposome/collagen precursor fluid, which, when heated from room
temperature to 37.degree. C., forms a mineralized collagen gel.
[0144] In some embodiments, the liposomes are loaded with
dipalmitoylphosphatidylcholine (90 mol %) and dimyristoyl
phosphatidylcholine (10 mol %). These liposomes are stable at room
temperature but form calcium phosphate mineral when heated above
35.degree. C., a consequence of the release of entrapped salts at
the lipid chain melting transition. One such technology is
disclosed in Pederson, Biomaterials 24: 4881-4890 (2003), the
specification of which is incorporated herein by reference in its
entirety.
[0145] Alternatively, the in situ mineralization of collagen could
be achieved by an increase in temperature achieved by other types
of reactions including, but not limited to, chemical, enzymatic,
magnetic, electric, photo- or nuclear. Suitable sources thereof
include light, chemical reaction, enzymatically controlled reaction
and an electric wire embedded in the material. To further elucidate
the electric wire approach, a wire can first be embedded in the
space, heated to create the calcium deposition, and then withdrawn.
In some embodiments, this wire may be a shape memory such as
nitinol that can form the shape. Alternatively, an
electrically-conducting polymer can be selected as the temperature
raising element. This polymer is heated to form the collagen, and
is then subject to disintegration and resorption in situ, thereby
providing space adjacent the mineralized collagen for the bone to
form.
[0146] In some embodiments, the osteoconductive material comprises
calcium and phosphorus. In some embodiments, the osteoconductive
material comprises hydroxyapatite. In some embodiments, the
osteoconductive material comprises collagen. In some embodiments,
the osteoconductive material is in a particulate form.
[0147] Specific matrices may be incorporated into the device to
provide load bearing qualities, enable directional bone formation,
and/or control density of regenerated bone (cortical vs cancellous)
or enable cell formation for soft tissue attachment. Nanotubes or
nanocrystals can be orientated in a generally axial direction to
provide for load bearing abilities as well as capillary wicking of
vascular flow to further enhance directional bone formation.
Biocompatible nanotubes can currently be produced from either
carbon or titanium or hone substitutes including Ca, HA, and
TCP.
[0148] In one embodiment, the bone forming agent is a plurality of
viable ex vivo osteoprogenitor cells. Such viable cells, introduced
into the interbody space, have the capability of at least partially
supplementing the in situ drawn stem cells in the generation of new
bone for the interbody space.
[0149] In some embodiments, these cells are obtained from another
human individual (allograft), while in other embodiments, the cells
are obtained from the same individual (autograft). In some
embodiments, the cells are taken from bone tissue, while in others,
the cells are taken from a non-bone tissue (and may, for example,
be mesenchymal stem cells, chondrocytes or fibroblasts). In others,
autograft osteocytes (such as from the knee, hip, shoulder, finger
or ear) may be used.
[0150] In one embodiment, when viable ex vivo cells are selected as
an additional therapeutic agent or substance, the viable cells
comprise mesenchymal stem cells (MSCs). MSCs provide a special
advantage for administration into the interbody space because it is
believed that they can more readily survive the relatively harsh
environment present in the space; that they have a desirable level
of plasticity; and that they have the ability to proliferate and
differentiate into the desired cells.
[0151] In some embodiments, the mesenchymal stem cells are obtained
from bone marrow, such as autologous bone marrow. In others, the
mesenchymal stem cells are obtained from adipose tissue, preferably
autologous adipose tissue.
[0152] In some embodiments, the mesenchymal stem cells injected
into the interbody space are provided in an unconcentrated form,
e.g., from fresh bone marrow. In others, they are provided in a
concentrated form. When provided in concentrated form, they can be
uncultured. Uncultured, concentrated MSCs can be readily obtained
by centrifugation, filtration, or immuno-absorption. When
filtration is selected, the methods disclosed in U.S. Pat. No.
6,049,026 ("Muschler"), the specification of which is incorporated
herein by reference in its entirety, can be used. In some
embodiments, the matrix used to filter and concentrate the MSCs is
also administered into the interbody space.
[0153] In some embodiments, bone cells (which may be from either an
allogeneic or an autologous source) or mesenchymal stem cells, may
be genetically modified to produce an osteoinductive bone anabolic
agent which could be chosen from the list of growth factors named
herein. The production of these osteopromotive agents may lead to
bone growth.
[0154] Recent work has shown that plasmid DNA will not elicit an
inflammatory response as does the use of viral vectors. Genes
encoding bone (anabolic) agents such as BMP may be efficacious if
injected into the uncoupled resorbing bone. In addition,
overexpression of any of the growth factors provided herein or
other agents which would limit local osteoclast activity would have
positive effects on bone growth. In one embodiment, the plasmid
contains the genetic code for human TGF-.beta. or erythropoietin
(EPO).
[0155] Accordingly, in sonic embodiments, the additional
therapeutic agent is selected from the group consisting of viable
cells and plasmid DNA.
[0156] A matrix may be made from hydrogels or may incorporate a
hydrogel as component of the final structure. A hydrogel may be
used to expand and enhance filling, improve handling
characteristics or increase vacuum pressure. The increased vacuum
pressure may be used to determine adequate hydration/stem cell
filtration.
[0157] In some cases, excess bone marrow aspirate can be collected
and mixed with added graft extenders including collagen like the
HEALOS.TM., and HEALOS FX.TM., each of which is available from
DePuy Synthes Spine, Raynham, Mass., USA.
[0158] In some embodiments, the bone growth agent is a synthetic
bone growth agent.
[0159] In sonic embodiments, the bone growth agent is a
non-autologous bone growth agent.
[0160] There are a number of ways in which the instruments and
devices of the present invention can be delivered from the
manufacturer to the surgeon. The instruments can be provided as
traditional non-sterile sets; in a sterile pack that is returned
for reprocessing and in a sterile pack that is single use. The
implants can be delivered sterile or non-sterile. The complete set
can be delivered sterile.
[0161] Although the present invention has been described with
reference to its preferred embodiments, those skillful in the art
will recognize changes that may be made in form and structure which
do not depart from the spirit of the invention.
* * * * *