U.S. patent application number 14/039628 was filed with the patent office on 2014-12-25 for cortical rim-supporting interbody device.
The applicant listed for this patent is Kevin Lee, Roman Lomeli. Invention is credited to Kevin Lee, Roman Lomeli.
Application Number | 20140378980 14/039628 |
Document ID | / |
Family ID | 52111503 |
Filed Date | 2014-12-25 |
United States Patent
Application |
20140378980 |
Kind Code |
A1 |
Lomeli; Roman ; et
al. |
December 25, 2014 |
Cortical Rim-Supporting Interbody Device
Abstract
A central inflatable distractor and a perimeter balloon are
inserted into the disc space in uninflated configurations. The
central inflatable distractor is then expanded, thereby distracting
the vertebral endplates to the controlled height of the central
inflatable distractor. The perimeter balloon is then inflated with
a curable substance. The perimeter balloon expands as it is filled
with the curable substance and conforms to the void remaining in
the disc space around the central inflatable distractor, thereby
creating a horseshoe shape. Once the flowable material in the
perimeter balloon has cured, the central inflated distractor can be
deflated and removed. The remaining void (or inner space) is then
packed with graft for fusion.
Inventors: |
Lomeli; Roman; (Plymouth,
MA) ; Lee; Kevin; (Canton, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Lomeli; Roman
Lee; Kevin |
Plymouth
Canton |
MA
MA |
US
US |
|
|
Family ID: |
52111503 |
Appl. No.: |
14/039628 |
Filed: |
September 27, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61838604 |
Jun 24, 2013 |
|
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|
Current U.S.
Class: |
606/90 |
Current CPC
Class: |
A61F 2002/30583
20130101; A61F 2002/2835 20130101; A61F 2310/00353 20130101; A61F
2/4611 20130101; A61F 2002/30011 20130101; A61F 2002/30556
20130101; A61F 2310/00359 20130101; A61F 2002/30581 20130101; A61F
2310/00293 20130101; A61F 2310/00365 20130101; A61F 2/442 20130101;
A61F 2002/30563 20130101; A61F 2310/00023 20130101; A61F 2310/00029
20130101; A61F 2002/30062 20130101; A61F 2002/444 20130101; A61F
2002/30016 20130101; A61B 17/8855 20130101; A61F 2002/30131
20130101; A61F 2310/00371 20130101; A61B 17/8811 20130101; A61F
2002/4435 20130101; A61F 2/4455 20130101; A61F 2002/4445 20130101;
A61B 17/7097 20130101; A61F 2002/30586 20130101; A61F 2/441
20130101; A61F 2002/30235 20130101; A61F 2002/30588 20130101; A61F
2002/30069 20130101; A61F 2002/30006 20130101; A61F 2002/302
20130101; A61F 2002/30331 20130101; A61F 2002/2817 20130101; A61F
2002/30579 20130101 |
Class at
Publication: |
606/90 |
International
Class: |
A61B 17/88 20060101
A61B017/88; A61F 2/44 20060101 A61F002/44 |
Claims
1. An instrument for forming an intervertebral fusion device
comprising: a) a distraction device comprising i) a first tube
having a distal end portion and ii) an inflatable distractor
attached to the distal end portion of the first tube, wherein the
inflatable distractor is filled with a biological inert fluid, b) a
fusion assembly comprising i) a second tube having a distal end
portion and ii) an inflatable balloon attached to the distal end
portion of the second tube, wherein the inflatable balloon is
filled with a curable material and has a height sized to span a
disc space, wherein the distal end portion of the first tube is
substantially adjacent the distal end portion of the second
tube.
2. The instrument of claim 1 further comprising: c) a delivery
cannula having a proximal end portion and a distal end portion;
wherein each tube is substantially received in the delivery cannula
so that the distal end of the first tube projects from the distal
end of the delivery cannula, and the distal end of the second tube
projects from the distal end of the delivery cannula.
3. The instrument of claim 1 wherein the balloon forms an annular
shape defining an inner space and the inflatable distractor is
disposed in the inner space.
4. The instrument of claim 1 wherein the balloon forms a
substantially horseshoe-shape defining an inner space and the
inflatable distractor is disposed in the inner space.
5. The instrument of claim 1 wherein the first and second tubes are
portions of a dual lumen tube.
6. The instrument of claim 1 wherein the inflatable distractor is
not integral with the inflatable balloon.
7. The instrument of claim 1 wherein the inflatable balloon has a
track associated therewith.
8. The instrument of claim 1 wherein the balloon is elastic.
9. The instrument of claim 1 wherein the balloon is inelastic and
forms a predetermined shape when inflated.
10. The instrument of claim 1 wherein the inflatable distractor has
a track associated therewith.
11. A method of forming an interbody fusion cage, comprising the
steps of; a) introducing an inflatable distractor into a disc space
in an uninflated form, b) inflating the inflatable distractor with
a biologically inert fluid to distract the disc space, c)
introducing an inflatable balloon into the disc space, d) filling
the inflatable balloon with a curable material;
12. The method of claim 11 further comprising the step of: e)
deflating the inflated distractor after the curable material has
cured.
13. The method of claim 12 further comprising the step of: f)
removing the deflated distractor from the disc space.
14. The method of claim 13, wherein the balloon has a substantially
annular form defining an inner space, further comprising the step
of: g) filling the inner space with an osteogenic material.
15. The method of claim 14 wherein the distractor occupies the
inner space defined by the balloon.
16. The method of claim 15 wherein the balloon is elastic.
17. The method of claim 15 wherein the balloon is inelastic and
forms a predetermined shape when inflated.
18. The method of claim 11 wherein the balloon forms an annular
shape.
19. The method of claim 11 wherein the balloon forms a
substantially horseshoe-shape.
20. The method of claim 11 wherein the balloon wraps around the
distractor so that an inner surface of the fusion balloon contacts
an outer perimeter of the inflated distractor.
21. A balloon assembly for treating an intervertebral disc space,
comprising: a) an inflated distractor having an outer perimeter and
being sized to distract the intervertebral disc space, the inflated
distractor filled with a biologically inert fluid, b) an inflated
fusion balloon forming a shape having an outer perimeter and an
inner surface, the fusion balloon filled with a curable material,
wherein the balloon wraps around the distractor so that the inner
surface of the fusion balloon contacts the outer perimeter of the
inflated distractor.
22. The assembly of claim 21 wherein the balloon forms an annular
shape defining an inner space and the inflated distractor is
disposed in the inner space.
23. The assembly of claim 21 wherein the balloon forms a
substantially horseshoe-shape defining an inner space and the
inflatable distractor is disposed in the inner space.
24. The assembly of claim 21 wherein the balloon is elastic.
25. The assembly of claim 21 wherein the balloon is inelastic and
forms a predetermined shape when inflated.
26. The assembly of claim 21 wherein the inner surface of the
fusion balloon is not integral with the outer perimeter of the
inflated distractor.
27. The assembly of claim 21 wherein the inflated distractor is
fluidly coupled with a hydraulic pressurizier capable of
pressurizing and de-pressurizing the distractor.
28. A balloon assembly for treating an intervertebral disc space,
comprising: a) a deflated distractor having an outer perimeter, b)
an inflated fusion balloon forming a shape having an outer
perimeter and an inner surface defining an inner space, the fusion
balloon filled with a cured material, the balloon being sized to
distract the intervertebral disc space, wherein the deflated
distractor is disposed within the inner space of the balloon.
29. A balloon assembly for treating an intervertebral disc space,
comprising: a) an inflated distractor having an outer perimeter and
filled with a biologically inert fluid, b) an inflated fusion
balloon forming a horsehoe-shape having an outer perimeter, an
inner surface defining an inner space and an open end, the fusion
balloon filled with a cured material, the balloon being sized to
distract the intervertebral disc space, wherein the inflated
distractor is disposed within the inner space of the balloon.
30. A method of preparing a disc space, comprising the steps of: a)
removing disc tissue to create a disc space; b) inserting the
central inflatable distractor into the disc space; c) expanding the
central inflatable distractor; d) inserting the perimeter balloon
into the disc space; e) introducing a curable material into the
perimeter balloon, and f) separating the perimeter balloon from its
second delivery tube.
31. The method of claim 30 further comprising the step of: g)
retracting the central inflatable distractor and removing it from
the disc space to create an inner space.
32. The method of claim 31, further comprising the step of: h)
filling the inner space with a flowable support material.
33. The method of claim 31 further comprising the steps of: h)
passing an instrument into the inner space, and i) performing a
task with the instrument.
34. The method of claim 30 further comprising the steps after step
c) of: g) passing an instrument into the disc space, and i)
performing a task with the instrument.
35. The method of claim 30 further comprising the step of: g)
injecting a support material into the central inflatable
distractor.
36. The method of claim 35 further comprising the step of: h)
separating the central inflatable distractor from a delivery
tube.
37. A device for preparing an intervertebral disc space,
comprising: a) an inflatable device sized to fit in the disc space,
b) an instrument attached to the inflatable device
38. The device of claim 37 wherein the instrument is attached to
the inflatable device by a track associated with the inflatable
device.
39. The device of claim 38 further comprising: c) a magnetic wheel
located on the track.
40. The device of claim 37 wherein the instrument is attached to
the inflatable device by a docking port associated with the
inflatable device.
41. The device of claim 37 wherein the instrument comprises a
distal docking element that mates with the docking port.
Description
[0001] This patent application claims priority from co-pending
application U.S. Ser. No. 61/838,604, entitled "Cortical
Rim-Supporting Interbody Device" (Lomeli et al.), filed Jun. 24,
2013 (DSP5012USPSP), the specification of which is incorporated by
reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] In an effort to treat low back pain, surgeon have removed
the degenerative disc and inserted a fusion cage into the disc
space. In an effort to minimize the invasiveness of the fusion
procedure, more recent efforts have focused upon forming the fusion
cage in-situ by flowing a curable material into a balloon that has
been placed into the disc space.
[0003] US Patent Publication 2004-0230309 (DePuy Spine) discloses
an orthopedic device for implanting between adjacent vertebrae
comprising: an arcuate balloon and a hardenable material within
said balloon. In some embodiments, the balloon has a footprint that
substantially corresponds to a perimeter of a vertebral endplate.
An inflatable device is inserted through a cannula into an
intervertebral space and oriented so that, upon expansion, a
natural angle between vertebrae will be at least partially
restored. At least one component selected from the group consisting
of a load-bearing component and an osteobiologic component is
directed into the inflatable device through a fluid communication
means. The FIG. 6B thereof discloses adjacent balloons in a disc
space.
[0004] U.S. Pat. No. 8,007,535 (Hudgins) discloses an injectable
annular ring useful in treating a deteriorating spinal disc. When
used, the annular ring may be collapsed or folded in order for it
to be placed through a small opening in a prepared intervertebral
space within the annulus using minimally invasive techniques.
Deployment or unfolding the ring in the intervertebral space
provides an interior cavity bordered by the ring that is in direct
contact with the vertebral endplates. When an internal volume of
the ring is injected or filled with a load-bearing, hardenable
material, the filled ring maintains the intervertebral spacing and
prevents the ring from being expelled from the interior cavity
through the small annular opening.
[0005] U.S. Pat. No. 6,332,894 (Stalcup) discloses an orthopaedic
implant for implanting between adjacent vertebrae and a spine,
includes a generally annular bag; and a hardened polymer within the
bag. The method of fusing adjacent vertebrae in a spine includes
the steps of forming an access hole in an annulus of a disc between
the adjacent vertebrae; removing the nucleus within the disc to
form a cavity surrounded by the annulus; placing a generally
annular bag within the cavity; filling the bag with a polymer;
injecting bone particles into the cavity surrounded by the annular
bag; and hardening the polymer.
[0006] US Published Patent Application 2003-0028251 (Mathews)
discloses methods and instruments for preparing a disc space and
for forming interbody devices therein. The instruments include
distractors having enlargeable portions positionable in the disc
space for distracting the disc space. The enlargeable portions can
also provide form about or against which an interbody device of a
first material is placed. A second material may be placed in the
disc space previously occupied by the distractors.
[0007] US Published Patent Application 2005-0119752 (Williams)
discloses devices and methods for manufacturing devices for
treating degenerated and/or traumatized intervertebral discs.
Artificial discs and components of discs may include an artificial
nucleus and/or an artificial annulus and may be comprised of shape
memory materials synthesized to achieve desired mechanical and
physical properties. An artificial nucleus and/or annulus according
to the invention may comprise one or more hollow bodies that may be
filled with a curable material for deployment. A hollow body
according to the invention may comprise one or more partitions to
define one or more chambers and may comprise means for directing
the flow of material within said hollow body. FIG. 19a of Williams
discloses a two-balloon design comprising a central balloon and a
perimeter balloon.
[0008] Subsidence of an implanted interbody cage is a known risk in
fusion and there is a higher occurance for patients with lower bone
density. Hou and Yuan, Spine Journal, 12, 3, 249-256 (2012)
investigated the structural properties of lumbar endplates and
reported that the periphery of the endplates particularly in the
posterolateral region near the pedicles were significantly stronger
than the central region. They also concluded that with increasing
disc degeneration, the central region became weaker while minimal
strength changes were observed in the peripheral region.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to percutaneously
deliver a peripheral structural support element that can sustain
loads immediately after surgery while allowing a central graft
column to form a complete fusion. The present invention relates to
a percutaneous delivery of a large footprint structural support
that contacts substantially only the apophyseal ring of the
endplates.
[0010] In accordance with the present invention, a central
inflatable distractor and a perimeter balloon are inserted into the
disc space in uninflated configurations. The central inflatable
distractor is then expanded, thereby distracting the vertebral
endplates to the controlled height of the central inflatable
distractor.
[0011] The perimeter balloon is then inflated with a curable
substance. The perimeter balloon expands as it is filled with the
curable substance and conforms to the void remaining in the disc
space around the central inflatable distractor, thereby creating a
horseshoe shape.
[0012] Once the flowable material in the perimeter balloon has
cured, the central inflated distractor can be deflated and removed.
The remaining void (or inner space) is then packed with graft for
fusion.
[0013] Therefore in accordance with the present invention, there is
provided an instrument for forming an intervertebral fusion device
comprising: [0014] a) a distraction device comprising i) a first
tube having a distal end portion and ii) an inflatable distractor
attached to the distal end portion of the first tube, wherein the
inflatable distractor is filled with a biological inert fluid,
[0015] b) a fusion assembly comprising i) a second tube having a
distal end portion and ii) an inflatable balloon attached to the
distal end portion of the second tube, wherein the inflatable
balloon is filled with a curable material and has a height sized to
span a disc space, wherein the distal end portion of the first tube
is substantially adjacent the distal end portion of the second
tube.
[0016] Therefore in accordance with the present invention, there is
provided a balloon assembly for treating an intervertebral disc
space, comprising: [0017] a) an inflated distractor having an outer
perimeter and being sized to distract the intervertebral disc
space, the inflated distractor filled with a biologically inert
fluid, [0018] b) an inflated fusion balloon forming a shape having
an outer perimeter and an inner surface, the fusion balloon filled
with a curable material, [0019] wherein the balloon wraps around
the distractor so that the inner surface of the fusion balloon
contacts the outer perimeter of the inflated distractor.
[0020] Therefore in accordance with the present invention, there is
provided a balloon assembly for treating an intervertebral disc
space, comprising:
a) a deflated distractor having an outer perimeter, b) an inflated
fusion balloon forming a shape having an outer perimeter and an
inner surface defining an inner space, the fusion balloon filled
with a cured material, the balloon being sized to distract the
intervertebral disc space, [0021] wherein the deflated distractor
is disposed within the inner space of the balloon.
DESCRIPTION OF THE FIGURES
[0022] FIGS. 1A-I disclose the step-wise process for making an
in-situ formed device in accordance with the present invention.
[0023] FIG. 2 discloses an annular perimeter balloon of the present
invention.
[0024] FIGS. 3A & 3B disclose flow charts for preferred steps
of the method of the present invention.
[0025] FIG. 4 discloses a cross-section of an MIS delivery of a
deflated balloon having a track.
[0026] FIG. 5 discloses a perspective view of an inflated balloon
having a track.
[0027] FIGS. 6A-6C disclose cross-sections of tracks of the present
invention.
[0028] FIG. 7 discloses a balloon of the present invention used as
a light source.
[0029] FIG. 8 discloses an assembly for passing instruments into
the inner space.
[0030] FIG. 9A discloses a track having cutouts.
[0031] FIGS. 9B-9E disclose cross-section of cutouts of the present
invention.
[0032] FIG. 10 discloses an inflated balloon having magnetic wheels
on its track.
[0033] FIGS. 11A-11B disclose cross-sections of
magnetic-wheel/track engagement.
[0034] FIG. 12 discloses an inflated balloon having a docking port
for docking an instrument.
DETAILED DESCRIPTION OF THE INVENTION
[0035] In a first step, and now referring to FIG. 1A, the surgeon
removes at least the nucleus pulposus portion of the disc targeted
for removal.
[0036] In a second step, and now referring to FIG. 1B, the central
inflatable distractor and the perimeter balloon are inserted into
the disc space and positioned in the central region thereof.
Typically, in this position, the perimeter balloon is wrapped
around the central inflatable distractor so that the inner surface
of the fusion balloon contacts the outer perimeter of the inflated
distractor.
[0037] In a third step, and now referring to FIG. 1C, the central
inflatable distractor is inflated and thereby separates the
vertebral endplates to a designated height.
[0038] In a fourth step, and now referring to FIG. 1D, a curable
material is flowed into the perimeter balloon. The balloon expands
around the inflated central distractor to both reach
circumferentially around the distractor and to contact the
vertebral endplates separated by the distractor. In essence, the
filled perimeter balloon takes up all of the void space created by
the inflation of the central distarctor.
[0039] In a fifth step, and now referring to FIG. 1E, the surgeon
waits while the curable material cures. In some cases, such as when
a conventional PMMA is used, this waiting period may be 5-20
minutes. In some embodiments, the surgeon can accelerate the curing
of the curable material by various energy means, including heating
it, using a chemical accelerant, light and vibrations.
[0040] In a fifth step, and now referring to FIG. 1F, the material
in the perimeter balloon is fully cured, and the central distractor
is deflated.
[0041] In a sixth step, and now referring to FIG. 1G, the deflated
central distractor is withdrawn, thereby leaving a horseshoe-shaped
structural support in the disc space. This horseshoe provides
support along the cortical rim of the vertebrae while leaving an
access point to the center of the disc space.
[0042] In a seventh step, and now referring to FIG. 1H, a tube is
inserted through the access point produced in the sixth step and
positioned near the center of the disc space. Graft material 11 is
then flowed through this tube and into the disc space, thereby
filling the void with graft.
[0043] In FIG. 1I, the graft fill tube is removed.
[0044] Therefore in accordance with the present invention, there is
provided of treating an intervertebral disc space, comprising the
steps of: [0045] a) introducing an inflatable distractor into a
disc space in an uninflated form, [0046] b) inflating the
inflatable distractor with a biologically inert fluid to distract
the disc space, [0047] c) introducing an inflatable balloon into
the disc space, [0048] d) filling the inflatable balloon with a
curable material; [0049] e) deflating the inflated distractor after
the curable material has cured to produce an inner space; [0050] f)
removing the deflated distractor from the disc space; and [0051] g)
filling the inner space with an osteogenic material.
[0052] Therefore in accordance with the present invention and now
referring to FIG. 1E, there is provided an instrument for forming
an intervertebral fusion device comprising: [0053] a) a distraction
device comprising i) a first tube 21 having a distal end portion 23
and ii) an inflatable distractor 1 attached to the distal end
portion of the first tube, wherein the inflatable distractor is
filled with a biological inert fluid, [0054] b) a fusion assembly
comprising i) a second tube 25 having a distal end portion 27 and
ii) an inflatable balloon 3 attached to the distal end portion of
the second tube, wherein the inflatable balloon is filled with a
curable material and has a height sized to span a disc space,
[0055] wherein the distal end portion of the first tube is
substantially adjacent the distal end portion of the second
tube.
[0056] Therefore in accordance with the present invention and now
referring to FIG. 1D, there is provided balloon assembly for
treating an intervertebral disc space, comprising: [0057] a) an
inflated distractor 1 having an outer perimeter 2 and being sized
to distract the intervertebral disc space, the inflated distractor
filled with a biologically inert fluid, [0058] b) an inflated
fusion balloon 3 forming a shape having an outer perimeter 4 and an
inner surface 5, the fusion balloon filled with a curable material,
wherein the balloon wraps around the distractor so that the inner
surface of the fusion balloon contacts the outer perimeter of the
inflated distractor, wherein the balloon forms an annular shape
defining an inner space and the inflated distractor is disposed in
the inner space.
[0059] Therefore in accordance with the present invention and now
referring to FIG. 1F, there is provided balloon assembly for
treating an intervertebral disc space, comprising:
a) a deflated distractor 1 having an outer perimeter, b) an
inflated fusion balloon 3 forming a shape having an outer perimeter
4 and an inner surface 5 defining an inner space 7, the fusion
balloon filled with a cured material, the balloon being sized to
distract the intervertebral disc space, wherein the deflated
distractor is disposed within the inner space of the balloon.
[0060] The purpose of the inflatable distractor is to distract the
collapsed disc space to a desirable height that restores the
physiologic spatial relationship of the adjacent vertebral bodies.
The inflatable distractor balloon may be provided in a multiplicity
of sizes to correspond to appropriate disc heights. In some
expanded embodiments, the central inflatable distactor has a
cylindrical shape comprising an annular intermediate portion
between two endfaces. In some expanded embodiments, the space
within the annular intermediate portion is filled with a
biologically inert distraction fluid, such as saline. The endfaces
may have roughened outer surfaces in order to better grip the
vertebral endplates. In some embodiments, the endfaces are
substantially parallel to each other in the inflated condition. In
others, the endfaces form an angle with each other (such as being 5
and 20 degrees) in order to provide a desirable amount of lordosis
to the disc space. The central inflatable distractor may be made
from the balloon materials disclosed in US Patent Publication
2004-0230309, the specification of which is incorporated by
reference in its entirety.
[0061] The perimeter balloon can be made of any conventional
material used for medical balloons. In some embodiments, it can be
nonporous. In other embodiments, it can be porous to allow some
cement to escape and thereby bond the support to the adjacent
tissue. In some embodiments, the perimeter balloon is resorbable
over time. The upper and lower surfaces of the perimeter balloon
may have roughened outer surfaces in order to better grip the
vertebral endplates. These roughened outer surfaces may include for
example, a plurality of teeth. The balloon may be made from the
balloon materials disclosed in US Patent Publication 2004-0230309,
the specification of which is incorporated by reference in its
entirety.
[0062] In one embodiment, the perimeter balloon is made of an
elastic material. This allows the balloon to be form-fitting as it
expands into the space between the central inflatable distractor
and the surviving annulus fibrosus. In other embodiments, the
balloon is inelastic and forms a predetermined shape when inflated.
Such an inelastic balloon may be beneficial because the
predetermined shape can be a horseshoe shape, and thereby allow the
structural support to extend around the perimeter of the central
inflatable distractor and rest upon the cortical rim.
[0063] In other embodiments, the perimeter balloon forms a
substantially horseshoe-shape. The horseshoe shape is advantageous
because it provides for a large surface area to rest upon the
cortical rim of the adjacent vertebral bodies, and its open end
allows for both withdrawal of the central deflated distractor and
delivery of the bone graft into the inner space. Preferably, the
perimeter balloon is made of a shape memory material that takes on
the shape of a horseshoe in its relaxed configuration. In other
embodiments, however, the horseshoe shaped perimeter balloon is
made of a conventional polymer having no shape memory
characteristics, and the balloon is simply manually curled around
the central inflatable distractor prior to its delivery into the
disc space, so that when the perimeter balloon enters the disc
space, it already has a substantially horseshoe shape.
[0064] In these horseshoe-shaped embodiments, the curable material
may be introduced into the perimeter balloon by a third tube whose
distal end is located within the perimeter balloon. The distal end
of this third tube is initially fully inserted into the perimeter
balloon and begins by filling the distal portion of the perimeter
balloon. As curable material fills the distal portion of the
perimeter balloon, the distal end of this third tube is withdrawn
proximally from the perimeter balloon at the same rate as the rate
of fill. This third tube thereby insures the complete filling of
the perimeter balloon. In other embodiments, the curable material
is simply flowed freeform into the proximal end opening of the
perimeter balloon and allowed to fill the perimeter balloon.
[0065] In one embodiment, the perimeter balloon forms an annular
shape. An annular perimeter balloon can be accomplished with the
technology disclosed in Stalcup's FIG. 4. The Stalcup technology
would need to be simply modified by adding a central inflatable
distractor at the distal end of Stalcup's first fill hose. Such an
annular embodiment is shown in FIG. 2 herein. The annular perimeter
balloon possesses a hole that allows for passage and withdrawl of
both the central inflatable distractor and a graft fill tube. The
advantage of an annular balloon is that it provides slightly more
surface area contact with the vertebral bodies than the horseshoe
shaped perimeter balloon, thereby reducing the stress upon the
structural support. It also provides for more even support, thereby
reducing stress heterogeneities.
[0066] In some embodiments, the system can be used without a
perimeter balloon, thereby allowing the cement to completely
conform to the remaining anatomy. In this embodiment, a catheter
could be used to evenly deposit the curable material. This catheter
can be steerable and independent of the central balloon, or guided
by the circumference of the central inflatable distractor via a
guidance system such as a channel, track or sleeve. This guidance
system around the central inflatable distractor can also be used to
guide tools and implants into the disc space. These tools can be
used to inspect the disc space, perform additional disc and annulus
removal, and place implants.
[0067] The curable substance that fills the perimeter balloon forms
a structural material capable of withstanding the physiologic axial
loads of the spine. In some embodiments, the curable material may
be a conventional bone cement, such as a PMMA cement, or a foaming
bone cement.
[0068] The graft that is deposited within the inner space can be
any graft suitable for fusing bone. The quantity of graft needed to
fill the inner space may be estimated from the volume of fluid in
the central distractor in its inflated configuration. This allows
the surgeon to prepare the proper amount of graft and avoid over-
or under-packing the inner space.
[0069] The delivery method and implant described herein may be
suitable for both complete and partial discectomy (i.e., with
annulus and ligament intact).
[0070] In some embodiments, it may be convenient to house each of
the tubes associated with the balloons within a larger cannula.
Housing these tubes within this larger cannula may ease the
minimally-invasive insertion of the tubes into the patient.
Therefore, in accordance with the present invention, there is
provided a delivery cannula having a proximal end portion and a
distal end portion;
wherein each tube is substantially received in the delivery cannula
so that the distal end of the first tube projects from the distal
end of the delivery cannula, and the distal end of the second tube
projects from the distal end of the delivery cannula.
[0071] Another method of simplifying the delivery of two tubes into
the disc space is through the use of a dual lumen tube. A dual
lumen tube has two bores that share the same medial wall.
Therefore, in some embodiments, the first and second tubes are
portions of a dual lumen tube.
[0072] In some embodiments, the graft material may be HEALOS FX, a
flowable collagen-based material available from DePuy Spine of
Raynham, Mass., USA.
[0073] In some embodiments, the graft material may comprises a bone
forming agent. 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.
[0074] 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 an 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.
[0075] 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.
[0076] In some embodiments, between about 1 ng and about 10 mg of
BMP are administered into the target disc space. In some
embodiments, between about 1 microgram (m) and about 1 mg of BMP
are administered into the target disc space.
[0077] In many preferred embodiments, the bone forming agent is a
porous matrix, and is preferably injectable.
[0078] 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 PLA, PDA, PEO, PEG, PVA, and capralactides), bone
substitutes (such as TCP, HA, and CaP), autograft, allograft,
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).
[0079] 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.
[0080] 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 bone growth around the
minerals such that osteointegration occurs.
[0081] 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.
[0082] 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 will provide the initial stability
required to treat pain in target tissues. 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.
[0083] In some embodiments, the porous matrix comprises a
resorbable polymeric material.
[0084] 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: [0085] 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 [0086] b) a second
formulation comprising liposomes containing calcium and
phosphate.
[0087] 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.
[0088] 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.
[0089] 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, vibration, focused ultrasound, 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.
[0090] 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.
[0091] 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 bone substitutes including Ca, HA, and
TCP.
[0092] 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.
[0093] 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.
[0094] 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.
[0095] 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.
[0096] 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.
[0097] 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.
[0098] 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).
[0099] Accordingly, in some embodiments, the additional therapeutic
agent is selected from the group consisting of viable cells and
plasmid DNA.
[0100] 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.
[0101] In all 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 Spine Inc, Raynham, Mass., USA.
[0102] Now referring to FIG. 3a, there is provided a flow chart of
some preferred methods of carrying out the present invention. In
general, this FIG. discloses the steps of: [0103] a) removing disc
tissue to create a disc space (bulk discectomy); [0104] b)
inserting the central inflatable distractor into the disc space;
[0105] c) expanding the central inflatable distractor; [0106] d)
inserting the perimeter balloon into the disc space; [0107] e)
introducing a curable material into the perimeter balloon, and
[0108] f) separating the perimeter balloon from its second delivery
tube.
[0109] In step c) above, the step of expanding can include
injecting a flowable support material (instead of saline) into the
central inflatable distractor. The flowable support material can be
selected from the group consisting of graft, hydrogels, curable
materials, artificial disc materials, autograft and allograft. This
injecting step can be followed by a step of separating the central
inflatable distractor from its (first) delivery tube so that it may
remain in the disc space.
[0110] In some embodiments, after step f), there may be a further
step of [0111] g) retracting the central inflatable distractor and
removing it from the disc space to create an inner space. In one
embodiment, step g) may be followed by a step of [0112] h) the
inner space with a flowable support material. The flowable support
material can be selected from the group consisting of graft,
hydrogels, curable materials, artificial disc materials, autograft
and allograft. In another embodiment, removal of the central
inflatable distractor (step g)) may be followed by: [0113] i)
passing an instrument into the inner space, and [0114] ii)
performing a task with the instrument. The passing of the
instrument into the inner space may be accomplished by utilizing a
track located upon the inner face of the perimeter balloon. The
instrument may be selected from the group consisting of a camera, a
light, a scraper, suction, irrigation, a rasp, a knife, grasping, a
burr, and a rotary cutter. The task may be selected from the group
consisting of inspection, disc removal, and endplate preparation.
Performance of the task may be followed by a step of [0115] a)
filling the inner space with a flowable support material. The
perimeter balloon may then be separated from its delivery tube by
cutting, unscrewing or breaking a way.
[0116] Now referring to FIG. 3b, there is provided a flow chart of
some other preferred methods of carrying; out the present
invention. In general, this FIG. discloses the steps of: [0117] a)
removing disc tissue to create a disc space (bulk discectomy);
[0118] b) inserting the central inflatable distractor into the disc
space; [0119] c) expanding the central inflatable distractor;
[0120] d) inserting the perimeter balloon into the disc space;
[0121] e) introducing a curable material into the perimeter
balloon, and [0122] f) separating the perimeter balloon from its
second delivery tube. Expanding the central inflatable distractor
(step c)) may be followed by: [0123] i) passing an instrument into
the disc space, and [0124] ii) performing a task with the
instrument. The passing of the instrument into the disc space may
be accomplished by utilizing a track located upon the outer face of
the central inflatable distractor. Instruments can be passed on
both sides of the central inflatable distractor. The instrument may
be selected from the group consisting of a camera, a light, a
scraper, suction, irrigation, a rasp, a knife, grasping, a burr,
and a rotary cutter. The task may be selected from the group
consisting of inspection, disc removal, endplate preparation,
cutting the annulus, cutting the Ali, cutting the PLL, and direct
decompression. Performance of the task may be followed by step
d)--inserting the perimeter balloon into the disc space. The
delivery of this balloon may also be accomplished by use of the
track.
[0125] The curable material of step e) can be selected from the
group consisting of graft, hydrogels, curable materials, artificial
disc materials, autograft and allograft.
[0126] The separation of step f) can be accomplished by cutting,
unscrewing or breaking away a section.
[0127] In some embodiments, the separation of step f) can be
followed by: [0128] g) injecting a support material into the first
device.
[0129] The support material of step g) can be selected from the
group consisting of graft, hydrogels, curable materials, artificial
disc materials, autograft and allograft.
[0130] In some embodiments, the injection of step g) can be
followed by [0131] h) separating the central inflatable distractor
from its delivery tube (so that it may remain in the disc
space).
[0132] Now referring to FIG. 4, there is provided an embodiment of
a balloon having a track associated therewith. Balloon 52 is
connected to balloon catheter 53 via connection/release point 55. A
track 57 wraps around the periphery of the balloon. This apparatus
is disposed within a delivery cannula 59.
[0133] Now referring to FIG. 5, there is provided a perspective
view of a deployed balloon 52 having a track 57. Balloon catheter
53 extends from the proximal portion of the balloon. Track 57 has a
central groove 59 for docking with an instrument.
[0134] FIGS. 6A-6C disclose different track cross sections. FIG. 6A
discloses a dual-sided track. FIG. 6B discloses a one-sided track.
FIG. 6C discloses a track having a trapezoidal cross-section.
[0135] FIG. 7 discloses an embodiment in which the central balloon
61 is used as a light source. The balloon is attached to a
light-transmitting catheter 65 that is housed within a delivery
catheter 63. Light is transmitted from light source 67 into the
light-transmitting catheter 65 and then into the balloon 61. In
some embodiments, the fluid used to inflate the central balloon can
include light-reflecting particles (not shown) in order to better
disperse the light. The light allows for easier inspection of the
disc space.
[0136] FIG. 8 discloses a step of passing an instrument 71 into the
inner space via a track 73 located on an interior surface 75 of the
perimeter balloon 77.
[0137] FIG. 9A discloses an embodiment of a track 81 that has
cut-outs 83. These cutouts provide a means for securing the
instrument. FIG. 9B discloses a cross-section of cutout 83. FIG. 9C
discloses a cross-section of a T-Track cutout 85. FIG. 91)
discloses a cross-section of a rolled-track cutout 87. FIG. 9E
discloses a cross-section of a C-track cutout 89.
[0138] FIG. 10 discloses an embodiment showing means for
transporting instruments along a track 91 on the central inflatable
balloon 93, A plurality of magnetic wheels 95 are shown travelling
along a track. These wheels can be used to transport instruments
into and from the disc space.
[0139] FIG. 11A shows details of how the magnetic wheel 101 can be
attached to the track. The wheel has a central magnet 103 that
contacts central rail 105 of the track 107. The overlap keeps the
instrument in line.
[0140] FIG. 11B shows another embodiment of the wheel-track
engagement, wherein the track has a pair of side rails 109 that
keep the wheel engaged.
[0141] FIG. 12 shows a pair of docking ports 111 bilaterally
disposed on a central inflatable balloon 113. An instrument 115 can
have a distal docking ball 117 for reception by the docking port.
In this case, the instrument has an articulating scraper 119
attached thereto for scraping tissue in the disc space.
* * * * *