U.S. patent application number 14/184967 was filed with the patent office on 2017-10-19 for interspinous process spacer apparatus and methods of use.
This patent application is currently assigned to ALPHATEC SPINE, INC.. The applicant listed for this patent is ALPHATEC SPINE, INC.. Invention is credited to WILLIAM REIMELS.
Application Number | 20170296237 14/184967 |
Document ID | / |
Family ID | 45871391 |
Filed Date | 2017-10-19 |
United States Patent
Application |
20170296237 |
Kind Code |
A9 |
REIMELS; WILLIAM |
October 19, 2017 |
INTERSPINOUS PROCESS SPACER APPARATUS AND METHODS OF USE
Abstract
An interspinous process spacer includes a main body, a first
wing, and a screw. The main body includes a first securing member
extending from a top portion of the main body that engages a first
vertebra and a bottom portion of the main body that engages a
second vertebra. The first wing pivotably couples to a distal
portion of the main body and includes a second securing member
extending parallel to the first securing member to form a first
clamp. The screw is positionable within the main body and includes
a distal end that positions the first wing between a first position
and a second position. The first clamp includes a first diameter in
the first position and a second diameter in the second
position.
Inventors: |
REIMELS; WILLIAM;
(Oceanside, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ALPHATEC SPINE, INC. |
Carlsbad |
CA |
US |
|
|
Assignee: |
ALPHATEC SPINE, INC.
Carlsbad
CA
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20150230835 A1 |
August 20, 2015 |
|
|
Family ID: |
45871391 |
Appl. No.: |
14/184967 |
Filed: |
February 20, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13240846 |
Sep 22, 2011 |
8702756 |
|
|
14184967 |
|
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|
61385800 |
Sep 23, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 17/7065 20130101;
A61B 17/7047 20130101; A61B 17/7067 20130101 |
International
Class: |
A61B 17/70 20060101
A61B017/70; A61B 17/70 20060101 A61B017/70 |
Claims
1. An interspinous process spacer, comprising: a main body
including a first securing member extending from a top portion of
the main body configured to engage a first vertebra; a first wing
pivotably coupled to a distal portion of the main body and
including a second securing member configured to engage the first
vertebra; the main body including a third securing member extending
from the bottom portion of the main body configured to engage a
second vertebra; a second wing pivotably coupled to a proximal
portion of the main body and including a fourth securing member
configured to engage the second vertebra; and a screw positionable
within the main body including a distal end that positions the
first wing between a first position wherein the first clamp
includes a first diameter and a second position wherein the first
clamp includes a second diameter, and a proximal end that positions
the second wing between a third position wherein the second clamp
includes a third diameter and a fourth position wherein the second
clamp includes a fourth diameter.
2. The interspinous process spacer of claim 1, wherein the distal
end of the screw includes a curved portion that engages a curved
section of the first wing and the proximal end of the screw
includes a threaded portion that engages a threaded bore in the
second wing.
3. The interspinous process spacer of claim 1, wherein the distal
end of the screw advances towards the distal portion to position
the first wing from the first position to the second position and
the proximal end of the screw rotates within the proximal portion
to position the second wing from the third position to the fourth
position.
4. The interspinous process spacer of claim 1, wherein the first
and third diameters are greater than thicknesses of spinous
processes of the first and second vertebrae and the second and
fourth diameters are less than the first and third diameters
respectively.
5. The interspinous process spacer of claim 1, wherein the first
and second wings pivotably couple to the main body by one of a
living hinge and a fixed axis of rotation.
6. A bilateral interspinous spacer comprising; a central portion; a
distal portion including a first wing positionable relative to the
central portion; a proximal portion including a second wing
positionable relative to the central portion; a top portion
including a first clamp section, wherein the first clamp section
includes a first clamp of the first wing and a second clamp, the
first clamp section including a first variable diameter between the
first clamp and the second clamp; and a bottom portion including a
second clamp section, wherein the second clamp section includes a
third clamp of the second wing and a fourth clamp, the second clamp
section including a second variable diameter between the third
clamp and the fourth clamp; wherein the first and second clamp
sections are configured to clamp between adjacent spinous processes
by positioning of the first and second wings.
7. The bilateral interspinous spacer of claim 6, further comprising
a screw positionable within the central portion and including a
distal end that positions the first wing between a first position
wherein the first variable diameter includes a first diameter and a
second position wherein the first variable diameter includes a
second diameter.
8. The bilateral interspinous spacer of claim 7, wherein the distal
end of the screw includes a curved portion that engages a curved
section of the first wing.
9. The bilateral interspinous spacer of claim 7, wherein the screw
advances towards the distal portion to position the first wing from
the first position to the second position.
10. The bilateral interspinous spacer of claim 7, wherein the first
wing pivotably couples to the central body by one of a living hinge
and a fixed axis of rotation.
11. The bilateral interspinous spacer of claim 7, wherein the first
diameter is greater than a thickness of a spinous process of the
first vertebra and the second diameter is less than the first
diameter.
12. The bilateral interspinous spacer of claim 12, wherein the
screw includes a proximal end that positions the second wing
between a third position wherein second variable diameter includes
a third diameter and a fourth position wherein the second variable
diameter includes a fourth diameter.
13. The bilateral interspinous spacer of claim 12, wherein the
proximal end of the screw includes a threaded portion that engages
a threaded bore of the second wing.
14. The bilateral interspinous spacer of claim 12, wherein the
screw advances towards the distal portion to position the second
wing from the third position to the fourth position.
15. The bilateral interspinous spacer of claim 12, wherein the
second wing pivotably couples to the central body by one of a
living hinge and a fixed axis of rotation.
16. The bilateral interspinous spacer of claim 12, wherein the
third diameter is greater than a thickness of a spinous process of
the second vertebra and the fourth diameter is less than the third
diameter.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/240,846, filed on Sep. 22, 2011 and entitled "Clamping
Interspinous Spacer Apparatus and Methods of Use" which claims
priority to U.S. Provisional Patent Application No. 61/385,800,
filed Sep. 23, 2010, both of which are incorporated herein by
reference.
FIELD
[0002] The present invention relates to the field of interspinous
devices, and more particularly, relates to an interspinous
apparatus inserted between two spinous processes of the lumbar
spine.
BACKGROUND
[0003] Lumbar Spinal Stenosis (LSS) is one of the most common
reasons for spine surgery in older people. Spinal stenosis is a
medical condition in which the spinal canal narrows and compresses
the spinal cord and nerves. This is usually due to the natural
process of spinal degeneration that occurs with aging. It may also
be caused by spinal disc herniation, osteoporosis, or a tumor.
Spinal stenosis may affect the cervical or lumbar vertebrae or
both. Lumbar spinal stenosis results in lower back pain as well as
pain or abnormal sensations in the legs, thighs, feet or buttocks,
or loss of bladder and bowel control.
[0004] Laminectomy is a basic part of the surgical treatment of LSS
and is an effective remedy for severe spinal stenosis. Laminectomy
can be done without spinal fusion; however, if the spinal column is
unstable, fusion may be required for the laminectomy.
[0005] Lumbar interspinous process decompression ("IPD"), also
known as interspinous distraction or posterior spinal distraction,
has been proposed as a minimally invasive alternative to
laminectomy and fusion. In IPD, an interspinous distraction
implant, also called a spacer, is inserted between the spinous
processes through a small (4-8 cm) incision. The supraspinous
ligament is maintained and assists in holding the implant in place,
such that no laminotomy, laminectomy, or foraminotomy is performed.
The device is intended to restrict painful motion while enabling
otherwise normal motion. The device theoretically enlarges the
neural foramen, decompresses the cauda equina, and acts as a spacer
between the spinous processes to maintain the flexion of the spinal
interspace.
[0006] Therefore, a device that can be implanted between two
spinous processes of the spine more easily and which involves less
invasive procedures than present day procedures is needed. Also, a
device which can easily be adapted for both fusion and non-fusion
procedures is needed. Such a device would aid in the treatment for
spinal stenosis. Current prior art devices are made of multiple
parts, are bulky, and require complex delivery instrumentations to
position, assemble and deploy a clamping apparatus. The present
invention attempts to solve these problems, as well as others.
SUMMARY OF THE INVENTION
[0007] Provided herein are systems, methods and apparatuses for a
clamping interspinous spacer. An interspinous process spacer
includes a main body, a first wing, and a screw. The main body
includes a first securing member extending from a top portion of
the main body that engages a first vertebra and a bottom portion of
the main body that engages a second vertebra. The first wing
pivotably couples to a distal portion of the main body and includes
a second securing member extending parallel to the first securing
member to form a first clamp. The screw is positionable within the
main body and includes a distal end that positions the first wing
between a first position and a second position. The first clamp
includes a first diameter in the first position and a second
diameter in the second position.
[0008] In other features, the distal end of the screw includes a
curved portion that engages a curved section of the first wing and
the proximal end of the screw includes a threaded portion that
engages a threaded bore in the main body. The screw advances
towards the distal portion to position the first wing from the
first position to the second position. The first diameter is
greater than a thickness of a spinous process of the first vertebra
and the second diameter is less than the first diameter. The first
wing pivotably couples to the main body by one of a living hinge
and a fixed axis of rotation.
[0009] In still other features, the interspinous process spacer
further includes a third securing extending from the bottom portion
of the main body that engages the second vertebra and a second wing
pivotably coupled to a proximal portion of the main body and
including a fourth securing member extending parallel to the third
securing member to form second clamp. The screw includes a proximal
end that positions the second wing between a first position and a
second position. The second clamp includes a first diameter in the
first position and a second diameter in the second position.
[0010] In other features, the distal end of the screw includes a
curved portion that engages a curved section of the first wing and
the proximal end of the screw includes a threaded portion that
engages a threaded bore in the second wing. The distal end of the
screw advances towards the distal portion to position the first
wing from the first position to the second position and the
proximal end of the screw rotates within the proximal portion to
position the second wing from the first position to the second
position. The first diameters are greater than thicknesses of
spinous processes of the first and second vertebrae respectively
and the second diameters are less than the first diameters. The
first and second wings pivotably couple to the main body by one of
a living hinge and a fixed axis of rotation.
[0011] In various embodiments, the interspinous process spacer
generally comprises a main body, a clamp section, and a slot,
wherein the main body includes a distal portion, a proximal
portion, a top portion, and a bottom portion; the distal portion
includes a first wing and the proximal portion includes a second
wing, the bottom portion includes a curved segment, top portion
includes the clamp section, wherein the clamp section includes a
first clamp and a second clamp; the first wing operably coupled to
the slot and the first clamp, wherein the slot generally extends
along the transverse axis of the main body; the slot includes a
slot opening located at or near the bottom portion and a slot
curvature at or near the top portion; and the clamp section and the
curved segment enable the interspinous spacer to be secured between
two spinous processes such that one spinous process rests in the
curved segment and another spinous process rests in the clamp
section.
[0012] The systems, methods, and apparatuses are set forth in part
in the description which follows, and in part will be obvious from
the description, or can be learned by practice of the methods,
apparatuses, and systems. The advantages of the methods,
apparatuses, and systems will be realized and attained by means of
the elements and combinations particularly pointed out in the
appended claims. It is to be understood that both the foregoing
general description and the following detailed description are
exemplary and explanatory only and are not restrictive of the
systems, methods, and apparatuses, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The foregoing and other features and advantages of the
invention are apparent from the following detailed description of
exemplary embodiments, read in conjunction with the accompanying
drawings. The detailed description and drawings are merely
illustrative of the invention rather than limiting, the scope of
the invention being defined by the appended claims and equivalents
thereof.
[0014] FIG. 1 is a perspective side view of the exterior portion
for one embodiment of the clamping interspinous spacer.
[0015] FIG. 2 is a cross-sectional view of one embodiment of the
clamping interspinous spacer showing the central screw 190 within
the central longitudinal lumen and the acceptor position and the
screw tube lumen within the central screw 190.
[0016] FIG. 3 is a cross-sectional view of one embodiment of the
clamping interspinous spacer showing the central screw 190
longitudinally displacing the first wing 140.
[0017] FIG. 4 is a cross-sectional view of one embodiment of the
clamping interspinous spacer showing the delivery position with the
cannulated threaded rod 200 engaging the proximal end of the
clamping interspinous spacer.
[0018] FIG. 5 is a cross-sectional view of one embodiment of the
clamping interspinous spacer showing the cannulated threaded rod
200 and the hex driver 230 inside the lumen 220 of the cannulated
threaded rod 200 to operably engage the inner surface of the
central screw 190.
[0019] FIG. 6 is a cross-sectional view of one embodiment of the
clamping interspinous spacer with the cannulated threaded rod 200
and the hex driver 230 operably engaged with the acceptor position
190.
[0020] FIG. 7A is a perspective view of the spinous processes 240
and the interspinous location 242 whereby a guide wire is delivered
with the interspinous spacer; FIG. 7B is a perspective view of the
spinous processes 240 whereby the interspinous spacer is placed
between adjacent spinous processes at a 90 degree angle with
respect to the z-axis; FIG. 7C is a perspective view of the
interspinous spacer rotated 90 degrees; and FIG. 7D is a
perspective view of the interspinous spacer deployed and clamped
onto the spinous process.
[0021] FIG. 8 is a perspective view of the exterior portion for one
embodiment of the bilateral interspinous spacer.
[0022] FIG. 9 is a cross-sectional view of one embodiment of the
bilateral interspinous spacer showing the central screw 390 within
the central longitudinal lumen and the acceptor position 386 and
the screw tube lumen 380 within the central screw 390.
[0023] FIG. 10 is a cross-sectional view of one embodiment of the
bilateral interspinous spacer showing the central screw 390 and the
guide wire 400 passing through the threaded portion, the screw
lumen, and the tapered hole 348.
[0024] FIG. 11 is a cross-sectional view of one embodiment of the
bilateral interspinous spacer showing the central screw 390
operably engaged with the screw driver 440 and the driver 410
operably engaged with the bilateral interspinous spacer.
[0025] FIG. 12 is a cross-sectional view of one embodiment of the
bilateral interspinous spacer showing the guide wire 400 passing
through the screw lumen and the driver 440 longitudinally
displacing the central screw 390 to deform the first wing 340 and
the second wing 342.
[0026] FIG. 13 is a perspective view of the exterior portion for
one embodiment of the bilateral interspinous spacer showing the
central screw 390 longitudinally displacing the first wing 340 and
the second wing 342.
[0027] FIGS. 14A and 14B are perspective views of the vertebrae
body and spinous process whereby the bilateral interspinous spacer
is delivered and deployed between adjacent spinous processes in
accordance with one embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0028] In the accompanying figures, like elements are identified by
like reference numerals among the several preferred embodiments of
the present invention.
[0029] Generally speaking, the clamping interspinous spacer 100
comprises a main body 110, a clamp section 120, and a slot 130, as
shown in FIG. 1. The main body 110 provides interspinous
distraction of the spinous process when implanted between adjacent
spinous processes, while the clamp section 120 and the slot 130
operate to clamp or secure the main body 110 between adjacent
spinous processes. The main body 110 includes a distal portion 112,
a proximal portion 114, a top portion 116, and a bottom portion
118. The clamping interspinous spacer 100 includes a transverse
axis 102, generally shown along the y-axis and along the proximal
portion 114 and the distal portion 112. The clamping interspinous
spacer 100 includes a longitudinal axis 104, which is generally
shown along the x-axis and along the top portion 116 and the bottom
portion 118. The clamping interspinous spacer 100 includes a
thickness generally along the z-axis, which may approximate the
thickness of a spinous process. The distal portion 112 includes a
first wing 140 and the proximal portion 114 includes a second wing
150. The bottom portion 118 includes a curved segment 160, which is
immovable relative to the second wing 150. The top portion 116
includes the clamp section 120 that is operably coupled to the
first wing 140, wherein the clamp section 120 includes a first
clamp 122 and a second clamp 124. The clamp section 120 includes a
diameter Dc between the first clamp 122 and the second clamp 124.
The first clamp 122 and the second clamp 124 may include inward
facing hooks or clasps 126 and 128 on the distal end of the clamps
122 and 124, respectively. The hooks 126 and 128 may include sharp
edges that act to secure the first clamp and second clamp 122 and
124 to outer portions or bony edges of the spinous process.
[0030] As shown in FIG. 1, the first wing 140 is operably coupled
to the slot 130 and the first clamp 122. The slot 130 includes a
length that generally extends from about the top portion 116 to the
bottom portion 118, while the slot 130 generally extends along the
longitudinal axis 102 of the main body 110, generally shown in the
y-direction. The slot 130 includes a slot opening 132 located at or
near the bottom portion 118 and a slot curvature 134 at or near the
top portion 116. The slot curvature 134 acts as a pivot point to
close and tighten the clamp section 120 when the slot 130 is
displaced or angulated. The slot 130, the clamp section 120, and
the curved segment 160 secure the clamping interspinous spacer 100
between two spinous processes that rest in the curved segment 160
and the clamp section 120. The main body 110 provides distraction
of the spinous process when implanted between adjacent spinous
processes by way of a cam action to restore original spinal column
height when the main body 110 is rotated about the longitudinal
axis 104.
[0031] As shown in FIG. 1, the main body 110 includes a rectangular
x-section on the exterior portion of the main body 110 that
provides for a sleek exterior to be passed through soft tissue with
minimal trauma. However, the exterior portion of the main body 110
may include alternative shaped-sections that are angled on the
periphery of the exterior, such as v-sections, square, oval, or
elliptical shapes in other embodiments. The exterior portion of the
main body 110 may be flat on the central portion with curved-in
outer sides in one embodiment. The first wing 140 and the second
wing 150 may generally be in a trapezoidal shape in one embodiment;
however, the first wing 140 and the second wing 150 may assume any
generally polygonal, triangular, or hexagonal shape in alternative
embodiments. The clamp section 120 may generally be in a U-shape,
or a C-shape in one embodiment; however, the clamp section 120 may
assume alternative shapes such as to conform to the spinous
process, such as V-shaped, cup-shaped, and the like. The clamp
section 120 may clamp down and secure the clamping interspinous
spacer onto any spinous process on the vertebrae, including, but
not limited to, the cervical, thoracic, lumbar, or sacral sections
of the vertebrae.
[0032] As shown in FIG. 2, the main body 110 includes a central
longitudinal lumen 170 extending along at least a potion of the
longitudinal axis of the main body 110, generally shown in the
x-axis direction in FIG. 2. The central longitudinal lumen 170
includes a threaded section 172, a curved section 174 and a distal
lumen 178. The lumen 170 may receive a central screw 190. The
threaded section 172 extends from the proximal portion 114 and
through the central portion of the main body 110 to the slot 130.
The threaded section 172 includes an opening 152 on the proximal
portion 114 of the second wing 150. The opening 152 is shaped to
allow the central screw 190 to operably couple to the threaded
section 172. The curved section 174 longitudinally extends from the
slot 130 towards the distal portion 112 and the first wing 140. The
slot 130 may be generally perpendicular to the central screw 190;
however, the slot 130 may be at an angle in relation to the central
screw 190. The central screw 190 includes a distal curved section
192, a central threaded portion 194, and a screw lumen 171
positioned coaxially within the central screw 190. The distal
curved section 192 operably engages the curved section 174 of the
first wing 140, such as to abut the curved section 174 and support
the first wing 140 during delivery and displace the first wing 140
during longitudinal movement of the central screw 190. The curved
section 174 and the distal curved section 192 are fitted to a
particular curvature in order for the first wing to deform along
the longitudinal and transverse axis. The central threaded portion
194 operably engages the threaded section 172 by a threading in a
screw-like fashion. Preferably, the distal curved section 192
includes a smaller diameter than the central threaded portion 194,
such that the central screw 190 may rotatably engage with the
threaded portion 172 of the central longitudinal lumen 170. The
screw lumen 171 is located concentrically within the central screw
190 and includes a proximal acceptor position 196 and a central
tube lumen 180, which are both coaxially positioned within the
central screw 190. The distal acceptor position 196 is shaped to
fit a screwdriver, preferably a hexagonal screwdriver in one
embodiment. The central tube lumen 180 includes a proximal end 182
and a distal end 184. The distal end 184 is operably coupled to the
distal lumen 178, where the distal lumen 178 is included within the
first wing 140. The distal lumen 178 includes an opening 142 on the
distal portion 112. The central tube lumen 180 and the distal lumen
178 longitudinally extend from the acceptor position 196 to the
opening 142 of the distal section 112, such that a guide wire (not
shown) may longitudinally extend through the central longitudinal
lumen 170 of the clamping interspinous spacer 100 for placement
between adjacent spinous processes.
[0033] The central threaded portion 194 of the central screw 190
concentrically engages the threaded section 172 to become
longitudinally movable by way of rotating the central screw 190 by
an operator, as shown in FIG. 3. Upon rotation of the central screw
190, the distal curved section 192 then proceeds to push or deform
the first wing 140 by pushing the curved section 174 along the
longitudinal axis and the transverse axis, which subsequently
deforms the first wing 140 along the longitudinal and transverse
axis and displaces the clamp 122 to tighten the clamp portion 120
onto a spinous process (not shown). The tightening of the clamp
portion 120 decreases the diameter Dc proportional to the distance
of the slot opening 132 and increases the diameter Ds of the slot
130. The diameters Dc and Ds may include a maximum and a minimum at
which they may increase and/or decrease. The slot curvature 134
acts as a pivot point to allow the first clamp 122 and the clamp
portion 120 to deform and angulate onto the spinous process.
Alternatively, the slot curvature 134 includes a hinge that is
coupled with the first clamp 122, the first wing 140, and the top
portion 116 of the main body. The hinge is a type of bearing that
connects the first clamp 122 and the first wing 140 with the top
portion 116 of the main body and allows only a limited angle of
rotation between them. As such, the first clamp 122 and the first
wing 140 connected by the hinge rotate relative to the top portion
116 of the main body 110 about a fixed axis of rotation. The hinge
may be made of flexible material such as a polymer or Nitinol,
titanium, and the like to allow for super elastic or plastic
deformation.
[0034] As shown in FIG. 4, the second wing 150 includes a first
lumen 154 and a second lumen 156, such as to receive a cannulated
rod 200 and to permit a screw driver to pass through a cannula 212
located coaxially within the cannulated rod 200. The cannulated
threaded rod 200 operably engages the proximal end of the threaded
section 172 as to abut the acceptor position 196. The cannulated
threaded rod 200 includes a distal threaded section 210 to
concentrically engage the threaded section 172 and the proximal
section 114 of the main body. The cannula 212 also passes through
the opening 152. The cannulated threaded rod 200 includes a top
flange 214 and a bottom flange 216 to concentrically seat and
secure the cannulated thread rod 200 into the first lumen 154 and
the second lumen 156 of the second wing 150.
[0035] During delivery, the clamping interspinous spacer 100 is
delivered over a guide wire 250 or kirschner wire ("k-wire") to an
interspinous location 242, generally shown in FIG. 7A. The clamping
interspinous spacer 100 is placed between adjacent spinous
processes 240 with the cannulated threaded rod 200, whereby the
clamp section 120 is pointing towards the z-axis or away from the
spine of the patient. Once the clamping interspinous spacer 100 is
between adjacent spinous processes 240, as shown in FIG. 7B, the
clamping interspinous spacer 100 is rotated 90 degrees by the
cannulated threaded rod 200 towards the y-axis or upwards towards
the patient's head or feet in the y-axis direction, which provides
a cam action to distend the vertebral bodies 244 and place the
clamp section 120 around the spinous process, as shown in FIG. 7C.
Once the clamp section 120 is around the spinous process a hex
driver 230 is slid inside a lumen 220 of the cannulated threaded
rod 200, whereby the hex driver 230 operably engages the inner
surface of the acceptor position 196 in the central screw 190 (not
shown) with a hexagonal screw portion 232, as shown in FIG. 5.
[0036] As shown in FIG. 6, the central screw 190 is operably
coupled with the hex driver 230 by way of the acceptor position
196, whereby an operator rotates the hex driver 230 to rotate the
central screw 190 and longitudinally advance the central screw 190
towards the distal portion 112, and increasing the diameter Ds of
the slot 130. The longitudinal displacement of the central screw
190 causes the first wing 140 to deform and thereby deform the
first clamp 122, which decreases the diameter Dc. The first clamp
122 clamps and tightens against the spinous process 240 to provide
increase stabilization for the spinal spacer and maintain
distraction of two spinous processes 240, generally shown in FIG.
7D. In one embodiment, the central screw 190 may be coupled with a
locking mechanism 198 as to prevent the backward movement of the
central screw 190, which would decrease the diameter Ds and
increase diameter Dc, as shown in FIG. 6. The locking mechanism 198
may be behind the central screw 190, which either may be a threaded
ring or the threaded portion 172 of the central lumen 170. The
threaded ring may be rotated in the central lumen 170 after the
central screw 190 has deformed the first wing 140 and the first
clamp 122. The threaded portion 172 may include a threaded lock
portion that maintains the central screw 190 from displacing
longitudinally backwards once the first wing 140 and the first
clamp 122 is deformed and engaged on the spinous process.
[0037] In an alternative embodiment, the interspinous spacer is
shown in a bilateral configuration 300. The bilateral interspinous
spacer 300 comprises a main body 310, a first clamp section 320, a
second clamp section 360, a first slot 330, and a second slot 350,
as shown in FIG. 8. The main body 310 provides interspinous
distraction of the spinous process when implanted between adjacent
spinous processes, while the first and second clamp sections 320
and 360 and first and second slots 330 and 350, respectively, and
operate to clamp or secure the main body 310 between adjacent
spinous processes. The central body 310 includes a distal portion
312, a proximal portion 314, a top portion 316, and a bottom
portion 318. The bilateral interspinous spacer 300 includes a
longitudinal axis 304, generally shown along the x-axis with the
proximal portion 314 and the distal portion 312. The bilateral
interspinous spacer 300 includes a transverse axis 302, which is
generally shown along the y-axis with the top portion 316 and the
bottom portion 318. The distal portion 312 includes a first wing
340 and the proximal portion 314 includes a second wing 342. The
bottom portion 318 includes the second clamp section 360, wherein
the second clamp section 360 includes a first clamp 362 and a
second clamp 364. The top portion 316 includes the first clamp
section 320, wherein the first clamp section 320 includes a first
clamp 322 and a second clamp 324. The first clamp section 320
includes a first diameter D1 and the first clamp 322 and the second
clamp 324 may include inward facing hooks or clasps 326 and 328 on
the distal end of the clamps 322 and 324, respectively. The second
clamp section 360 includes a second diameter D2 and the first clamp
362 and the second clamp 364 may include inward facing hooks or
clasps 366 and 368 on the distal end of the first and second clamps
362 and 364, respectively. The hooks 366 and 368 may include sharp
edges that act to secure the first clamp and second clamp 122 and
124 to outer portions or bony edges of the spinous process.
[0038] As shown in FIG. 8, the first wing 340 is operably coupled
to the first slot 330 and the first clamp 322. The second wing 342
is operably coupled to the second slot 350 and the second clamp
364. The first slot 330 generally comprises a first leg 332 and a
second leg 334 in an L-shape, where the first leg 332 extends along
the transverse axis of the main body 310 and the second leg 334
extends along the longitudinal axis of the main body 310. The
transverse axis is generally shown in the y-direction and the
longitudinal axis is generally shown in the x-direction. The first
and second leg 332 and 334 may be perpendicular with respect to
each other; however, the first and second leg 332 and 334 may at an
angle greater or less than 90 degrees with respect to each other.
The angle with respect to the first and second leg 332 and 334 may
be selected as to permit the first wing 340 to deform at a
particular angle or distance. The second slot 350 generally
comprises a first leg 352 and a second leg 354 in an L-shape, where
the first leg 352 extends along the transverse axis of the main
body 310 and the second leg 354 extends along the longitudinal axis
of the main body 310. The first and second leg 352 and 354 may be
perpendicular with respect to each other; however, the first and
second leg 352 and 354 may at an angle greater or less than 90
degrees with respect to each other. The first and second slots 330
and 350 are shaped as to allow the first and second wings 340 and
342 to deform, respectively. The first and second slots 330 and 350
may generally alternative shapes, such as V-shaped, C-shaped, and
the like.
[0039] As shown in FIG. 8, the first slot 330 includes a slot
opening 336 located at or near the distal portion 312 and the
second slot 350 includes a slot opening 356 at or near the proximal
portion 314. The first clamp section 320 and the second clamp
section 360 enable the bilateral clamping interspinous spacer 300
to be secured between two adjacent spinous processes, such that one
spinous process rests in the first clamp section 320 and a second
spinous process rests in the second clamp section 360. The second
leg 334 extends from the middle section of the main body to the
exterior edge of the distal portion 312, while the second leg 356
extends from the middle section of the main body to the exterior
edge of the proximal portion 314. In one embodiment, the main body
310 includes a rectangular cross-section on the exterior portion of
the main body 310; however, the exterior portion of the main body
110 may include alternative sections, such as v-sections, square,
oval, or elliptical shapes. The exterior portion of the main body
310 may be flat on the central portion with proximal and distal
sides curved-in towards the interior of the main body 310. The
first wing 340 and the second wing 342 may generally be in a
trapezoidal shape; however, the first wing 340 and the second wing
342 may assume any generally polygonal, triangular, or hexagonal
shape. The first clamp section 320 and the second clamp section 360
may generally be in a U-shape or C-shape in one embodiment;
however, the clamp sections 320 and 360 may assume alternative
shapes such as to conform to the spinous process, such as V-shaped,
cup-shaped, and the like.
[0040] As shown in FIG. 9, the main body 310 includes a central
longitudinal lumen 370 extending along at least a potion of the
longitudinal axis of the central body 310, generally shown in the
x-axis direction in FIG. 9. The central longitudinal lumen 370
includes a threaded section 372, a curved section 378, and a wing
lumen 346. A central screw 390 is coaxially engaged within the
central longitudinal lumen 370 from the threaded section 372 to the
curved section 378. The threaded section 372 extends from the
proximal portion 314 and through the second wing 342. The threaded
section 372 includes an opening 356, which is included in the
proximal portion 114 of the second wing 342. The curved section 378
longitudinally extends from the first slot 330 to the distal
portion 312 and in the first wing 340.
[0041] As shown in FIG. 9, the central screw 390 includes a central
tube 380, which is a tubular opening coaxially within the central
screw 390 with a proximal end 382 and a distal end 384. The first
wing 340 includes the wing lumen 346 to operably couple the distal
end 384 of the central tube 380 and form a contiguous lumen
therebetween. The central screw 390 includes a distal curved
portion 392, a screw acceptor portion 386, and a threaded proximal
portion 394. The central tube 380 longitudinally extends from the
screw acceptor portion 386 to the distal portion 392 of the central
screw 190. The screw acceptor portion 386 extends to the proximal
portion of the central screw 390 to accept a screw like or
hexagonal screw device.
[0042] As shown in FIG. 10, the first clamp section 320 and the
second clamp section 360 include diameters D1 and D2, respectively,
which may include a maximum and a minimum at which the diameters D1
and D2 may increase and decrease. The first slot 330 includes a
first slot curvature 338 that acts as a pivot point to allow the
first wing 340 to deform and angulate. The second slot 350 includes
a second slot curvature 358 that acts as a pivot point to allow the
second wing 342 to deform and angulate. Alternatively, the slot
curvatures 338 and 358 include a hinge, whereby the slot curvature
338 that is hinge is coupled with the first clamp 322, the first
wing 340, and the top portion 316 of the main body 310. The slot
curvature 358 that is a hinge is coupled with the second clamp 364,
the second wing 342, and the bottom portion 318 of the main body
310. The hinge is a type of bearing that connects the first clamp
322 and the first wing 340 with the top portion 316 of the main
body and allows only a limited angle of rotation between them. As
such, the first clamp 322 and the first wing 340 connected by the
hinge rotate relative to the top portion 316 of the main body about
a fixed axis of rotation. Likewise, the second clamp 364 and the
second wing 342 connected by the hinge rotate relative to the
bottom portion 318 of the main body about a fixed axis of rotation.
The hinge may be made of flexible material such as a polymer or
Nitinol, titanium, and like to allow for super elastic or plastic
deformation.
[0043] As shown in FIG. 10, the threaded proximal portion 394 of
the central screw 390 is tapered at an angle with respect to the
longitudinal axis, in order to allow the second wing 342 to
angulate or deform at an angle when the central screw 390 is
rotated to concentrically engage the threaded section 372, thus
becoming longitudinally movable by way of rotating the central
screw 390. Alternatively, the threaded portion 372 of the second
wing 342 may be tapered at an angle with respect to the
longitudinal axis, such that the second wing 342 is able to
angulate or deform when the central screw 390 is rotated. In one
embodiment, both the threaded proximal portion 394 and the threaded
portion 372 of the second wing 342 are tapered at an angle with
respect to the longitudinal axis, such as to allow the second wing
342 to angulate or be deformed at an angle when the central screw
390 is rotated. Alternatively, the threaded portion 372 of the
second wing 342 are tapered at the same angle with respect to the
longitudinal axis, such as to allow the second wing 342 to angulate
or be deformed at an angle when the central screw 390 is
rotated.
[0044] As shown in FIG. 10, the central screw 390 includes a screw
lumen 396 that extends substantially through the longitudinal axis
of the central screw. The screw lumen 396 coaxially extends through
the central tube 380 and the screw acceptor portion 386, as shown
in FIG. 9. The wing lumen 346 in the first wing 340 includes a
tapered edge 348 in the distal portion. A guide wire or K-wire 400
passes through the screw lumen 396 during delivery and through the
wing lumen 346 and tapered edges 348, such that the K-wire does not
get trapped or caught as the first wing 340 angulates or deforms.
The proximal portion 314 includes a first driver lumen 412 and a
second driver lumen 414 to accept a driver 410, as shown in FIG.
11. The first driver lumen 412 is positioned in the second clamp
324 of the first clamp section 320, while the second driver lumen
422 is positioned in the second wing 342.
[0045] The central screw 390, as shown in FIG. 11, operably engages
the central longitudinal lumen 370, whereby the distal curved
portion 392 abuts the curved section 378 and supports the first
wing 340 during delivery of the bilateral clamping interspinous
spacer 300. The driver 410 includes a first drive portion 420 and a
second drive portion 422 to operably engage the first driver lumen
412 and the second driver lumen 414, respectively. During a 90
degree rotation of the bilateral clamping interspinous spacer 300,
the driver 410 gains traction and adhesion to rotate the bilateral
interspinous spacer 300 about the z-axis. Thus, both the first
clamp section 320 and the second clamp section 360 are secured by
the driver 410. The driver 410 includes a central drive lumen 430
and a drive threaded portion 432 that is coaxially located in the
central portion of the driver 410. The drive threaded portion 432
concentrically engages the threaded portion 372 of the proximal
portion 314 of the main body 310. The central drive lumen 430
allows for the passageway for a screwdriver 440 to operably engage
the acceptor portion 386 of the central screw 390.
[0046] As shown in FIG. 12, the driver 410 is removed from the
first and second driver lumens 420 and 422, while the screwdriver
440 remains operably engaged with the central screw 390. The
bilateral interspinous spacer 300 is deployed when an operator
rotates the screwdriver 440 to longitudinally displace the central
screw 390 and cause the first wing 340 to deform and angulate the
first clamp 322 in the x-direction towards the proximal section 314
of the main body 310, while the second wing 342 deforms and
angulates the second clamp 364 in the x-direction towards the
distal section 312 of the main body 310. As such, the diameter D1
of the first clamp section is decreased by a proportional amount of
the central screw's 390 longitudinal movement by the screwdriver
440, and the diameter D2 is also decreased by a proportional amount
of the central screw 390 longitudinal movements by the screwdriver
440. The first slot curvature 338 and the second slot curvature 352
act as pivot points to allow the first wing 340 and the second wing
342 to deform and angulate, respectively. Accordingly, the first
leg 352 and the second leg 354 of the second slot 350 increase in
diameter when the second wing 342 deforms along the transverse axis
of the main body 310. And the first leg 332 and the second leg 334
of the first slot 330 increase in diameter when the first wing 340
deforms along the transverse axis of the main body 310. In one
embodiment, the central screw 390 may be coupled with a locking
mechanism 398 as to prevent the backward movement of the central
screw 390, which would decrease the diameter of the first and
second slots 330 and 350 and increase diameters D1 and D2, as shown
in FIG. 12. The locking mechanism 398 may be behind the central
screw 390, which either may be a threaded ring or the threaded
portion 372 of the central lumen 370. The threaded ring may be
rotated in the central lumen 370 after the central screw 390 has
deformed the first wing 340 and the second wing 342. The threaded
portion 372 may include a threaded lock portion that maintains the
central screw 390 from displacing longitudinally backwards once the
first wing 340 and the second wing 342 is deformed and engaged on
the spinous processes.
[0047] As shown in FIG. 13, when the central screw 390 is
longitudinally displaced, the first wing 340 and the second wing
342 are angulated as to clamp the bilateral interspinous spacer 300
with the first clamp 322 and the second clamp 364 on the top and
bottom portions, respectively. The first and second clamp sections
clamp down and secure the bilateral interspinous spacer onto two
spinous processes. The distance between the first and second clamp
sections may be modified to secure the bilateral interspinous
spacer between two spinous processes along the vertebrae section,
including, but not limited to, the cervical, thoracic, lumbar, or
sacral sections of the vertebrae.
[0048] During delivery, the bilateral interspinous spacer 300 is
delivered over a guide wire 250 or kirschner wire ("k-wire"),
generally shown in FIG. 14A. The bilateral interspinous spacer 300
is placed between adjacent spinous processes 240 with the driver
410, whereby the first clamp section 320 is pointing towards the
z-axis or away from the spine of the patient. Once the bilateral
interspinous spacer 300 is between adjacent spinous processes 240,
as shown in FIG. 14A, the bilateral interspinous spacer 300 is
rotated 90 degrees by the driver 410 towards the y-axis or upwards
towards the patient's head or feet in the y-axis direction, which
provides a cam action to distend the vertebral bodies 244 and place
the first clamp section 320 and the second clamp section 360 around
the spinous process, as shown in FIG. 14B. Once the first clamp
section 320 and the second clamp section 360 are around adjacent
spinous processes, the hex driver 410 operably engages the central
screw 390 and longitudinally displaces the central screw 390 to
angulate or deform the first wing 340 and the second wing 342 onto
the spinous processes.
[0049] Optionally, before the interspinous spacers 100 or 300 is
deployed and implanted, provisional dilation of the spinous
processes 240 is performed with cannulated conical screw or smooth
semi conical shape dilators. During provisional dilation, the first
dilator is inserted via the guide wire and cuts through the
interspinous ligament using the sharp edges. The dilator distracts
the spinous processes 240 if the dilator comes into contact with
the spinous processes 240. Then, the first dilator is removed.
[0050] If the first dilator does not contact the spinous processes
240, a second dilator is inserted via the guide wire. The second
dilator is larger than the first dilator and also cuts through the
interspinous ligament. If necessary, several dilators, etc. can be
used until one of the dilators contacts the spinous processes 240.
The dilators can have slightly increasing outer diameters. For
example, a 6 mm, an 8 mm, a 10 mm, a 12 mm, and a 14 mm dilator can
be used. Contact between the dilator and the spinous processes 240
can be felt due to the tension provided between the spinous
processes 240 by the super spinous ligament. Once the proper size
is determined by the dilator, a distractor of an appropriate size
can be selected.
[0051] As can be understood by one skilled in the art, the clamping
interspinous spacer 100 and the bilateral interspinous spacer 300
and/or any of its components may have any size, shape, length,
thickness, height, weight, or any other parameters. Such parameters
may be selected by the surgeon (or other qualified professional)
for performance of specific procedures. Further, the clamping
interspinous spacer 100 and the bilateral interspinous spacer
and/or any of its components may be manufactured from metal,
plastic, synthetic material, or other suitable materials, or any
combination thereof. Preferably, the interspinous spacers 100 and
300 are formed from polyether ether ketone (PEEK), which is a
colorless organic polymer thermoplastic. Alternatively, the
interspinous spacers 100 and 300 are formed from Nitinol or
titanium, stainless steel, or other shape memory metal
materials.
[0052] The embodiments disclosed herein seeks to minimize the
number of component parts of the implant by using a flexible
material such as PEEK plastic to create a "living" hinge within the
body of the implant. The implant is clamped by activating the
central screw that causes the clamp sections of the implant to
pivot, close, and tighten against the spinous process. By using an
oblong cross-section at the root of the jaws the implant can
provide distraction of the spinous process by rotating it 90
degrees. This cam action helps restore original spinal column
height while rotating the jaws into position around the spinous
process. The implant can be designed with a single jaw or dual jaws
which mimic the wing component of existing spinous process
clamps.
[0053] The one piece body design with integral wings allows the
creation of a sleek exterior which can be passed through soft
tissue with minimal trauma. The implant may be delivered in a
minimally invasive surgery (MIS) or an open surgery. The implant
can be delivered over a K-wire which provides extra security and
guides the implant into the propel position. Simply rotating the
implant 90.degree. positions the jaws between the spinous process
and provides cam action to distend the vertebral bodies. The
implant design is comprised of only the implant body and an
activation screw minimizing any chance of movable parts coming
loose and causing a complication in surgery. The delivery
instrumentation is uncomplicated and comparable to the well proven
interbody instrumentation consisting of an outer member secured to
the implant and an internal means of rotating the actuation screw.
The implant can be used alone or as a supplement to other spinal
procedures.
[0054] While the invention has been described in connection with
various embodiments, it will be understood that the invention is
capable of further modifications. This application is intended to
cover any variations, uses, or adaptations of the invention
following, in general, the principles of the invention, and
including such departures from the present disclosure as, within
the known and customary practice within the art to which the
invention pertains.
* * * * *