U.S. patent application number 16/837493 was filed with the patent office on 2020-08-06 for intervertebral implant with integrated fixation.
The applicant listed for this patent is Howmedica Osteonics Corp.. Invention is credited to Hyun Bae, Joshua A. Butters, Rick B. Delamarter, Dylan Hushka, Daniel F. Justin, Nicholas Slater.
Application Number | 20200246163 16/837493 |
Document ID | / |
Family ID | 1000004769595 |
Filed Date | 2020-08-06 |
United States Patent
Application |
20200246163 |
Kind Code |
A1 |
Bae; Hyun ; et al. |
August 6, 2020 |
Intervertebral Implant With Integrated Fixation
Abstract
A surgical instrument and method for inserting a spinal implant
in the intervertebral disc space between two adjacent vertebrae and
an anchor engageable with the implant and an adjacent vertebra are
provided. The instrument includes an inserter having an engagement
portion including a distal engagement surface for interfacing with
the implant and a handle portion. The engagement portion includes a
track for slidably translating the anchor toward the engagement
surface. A kit is provided including the inserter and a tamp to
force the anchor into engagement with the implant and the adjacent
vertebra. The kit may also include a cutter for piercing the
adjacent vertebra.
Inventors: |
Bae; Hyun; (Santa Monica,
CA) ; Slater; Nicholas; (Chandler, AZ) ;
Butters; Joshua A.; (Chandler, AZ) ; Justin; Daniel
F.; (Orlando, FL) ; Hushka; Dylan; (Chandler,
AZ) ; Delamarter; Rick B.; (Los Angeles, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Howmedica Osteonics Corp. |
Mahwah |
NJ |
US |
|
|
Family ID: |
1000004769595 |
Appl. No.: |
16/837493 |
Filed: |
April 1, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15645298 |
Jul 10, 2017 |
10687964 |
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16837493 |
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13389298 |
Jul 16, 2012 |
9700434 |
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PCT/US2010/044988 |
Aug 10, 2010 |
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15645298 |
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61257734 |
Nov 3, 2009 |
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61257667 |
Nov 3, 2009 |
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61232705 |
Aug 10, 2009 |
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61232745 |
Aug 10, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/305 20130101;
A61F 2230/0052 20130101; A61F 2/4455 20130101; A61F 2002/30593
20130101; A61F 2002/30884 20130101; A61F 2002/30736 20130101; A61F
2002/30367 20130101; A61F 2/4611 20130101; A61F 2/447 20130101;
A61F 2002/30879 20130101; A61F 2002/4627 20130101; A61F 2002/30352
20130101; A61F 2002/30841 20130101; A61F 2002/30528 20130101; A61F
2002/30172 20130101; A61F 2220/0033 20130101; A61F 2220/0025
20130101; A61F 2002/30387 20130101; A61F 2/30734 20130101; A61F
2002/4629 20130101; A61F 2002/30845 20130101; A61F 2002/30904
20130101; A61F 2002/30166 20130101; A61F 2230/0028 20130101; A61F
2002/30738 20130101; A61F 2002/30401 20130101 |
International
Class: |
A61F 2/46 20060101
A61F002/46; A61F 2/44 20060101 A61F002/44 |
Claims
1. (canceled)
2. A method of inserting an implant in the intervertebral disc
space between two adjacent vertebrae and an anchor engageable with
the implant and an adjacent vertebra, the method comprising the
steps of: attaching a distal end of an inserter to the implant;
inserting the implant into the disc space by manipulating the
inserter; and inserting an anchor along a track exposed at a
surface of the inserter and into engagement with the implant and
the adjacent vertebra, such that while the anchor is disposed
within the track, the anchor extends above the surface as it
translates along the inserter, wherein the step of inserting the
anchor includes compressing the adjacent vertebra against the
implant.
3. The method of claim 2, further comprising a step of sliding a
tamp along the inserter in contact with the anchor to force the
anchor into engagement with the implant and the adjacent
vertebra.
4. The method of claim 3, wherein the step of sliding the tamp
includes impacting a proximal end of the tamp.
5. The method of claim 2, further comprising a step of impacting a
proximal end of an instrument that is in contact with the
anchor.
6. The method of claim 2, further comprising a step of applying an
impaction force to the anchor.
7. The method of claim 2, further comprising a step of cutting an
entryway into the adjacent vertebra for the anchor.
8. The method of claim 7, wherein the step of cutting includes
sliding a cutter along the inserter and piercing the adjacent
vertebra.
9. The method of claim 2, wherein the step of attaching includes
securing the implant to the distal end of the inserter by inserting
a rod of the inserter into an aperture of the implant.
10. The method of claim 9, wherein the step of inserting the rod
includes screwing a threaded portion of the rod into a threaded
portion of the aperture.
11. The method of claim 2, wherein the step of inserting the
implant includes impacting a proximal end of the inserter.
12. The method of claim 2, wherein the step of inserting the anchor
includes locking the anchor to the implant to prevent migration and
backout of the anchor with respect to the implant.
13. The method of claim 2, wherein the step of inserting the anchor
includes locking the anchor to the adjacent vertebra to prevent
migration and backout of the anchor with respect to the adjacent
vertebra.
14. The method of claim 2, wherein the anchor prevents axial
movement along an axis of the spine between the implant and the
adjacent vertebra.
15. The method of claim 2, wherein the anchor prevents torsional
movement between the implant and the adjacent vertebra.
16. The method of claim 2, further comprising a step of inserting a
second anchor into engagement with the implant and the opposing
adjacent vertebra.
17. The method of claim 16, further comprising a step of cutting an
entryway into the opposing adjacent vertebra for the second
anchor.
18. The method of claim 2, further comprising a step of packing a
chamber of the implant with graft material.
19. The method of claim 2, further comprising steps of: providing a
kit of differently sized and shaped implants and anchors; and
selecting an implant and an anchor according to the anatomy of the
patient.
20. The method of claim 2, wherein the step of inserting the anchor
causes an interconnection portion of the anchor to engage the
implant and a fixation portion of the anchor spaced apart from the
interconnection portion to engage the adjacent vertebra, wherein
the fixation portion is configured to track along a path into the
adjacent vertebra that diverges from a path into the implant taken
by the interconnection portion as the anchor slides into engagement
with the implant and the adjacent vertebra.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a divisional of U.S. patent
application Ser. No. 15/645,298, filed on Jul. 10, 2017, which is a
continuation of U.S. patent application Ser. No. 13/389,298, now
U.S. Pat. No. 9,700,434, filed on Feb. 7, 2012, which is a national
phase entry under 35 U.S.C. .sctn. 371 of International Application
No. PCT/US10/44988 filed Aug. 10, 2010, published in English, which
claims priority from U.S. Provisional Patent Application No.
61/232,705 filed Aug. 10, 2009, entitled Intervertebral implant
with integrated fixation, U.S. Provisional Patent Application No.
61/232,745 filed Aug. 10, 2009, entitled Intervertebral implant
with integrated fixation, U.S. Provisional Patent Application No.
61/257,734 filed Nov. 3, 2009, entitled Intervertebral implant with
integrated fixation including an instrument for implant revision,
and U.S. Provisional Patent Application No. 61/257,667 filed Nov.
3, 2009, entitled Intervertebral implant with integrated fixation,
the disclosures of which are hereby incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to spinal surgery. More
particularly, the present invention relates to surgical instruments
and a method of using such instruments to insert an implant and
anchors into the intervertebral disc space and the adjacent
vertebrae.
[0003] Back pain can be caused by many different things, including
any one of several problems that affect the intervertebral discs of
the spine. These disc problems include, for instance, degeneration,
bulging, herniation, thinning of a disc, and abnormal movement, and
the pain that is experienced is generally attributable to friction
or pressure that inevitably occurs when one adjacent vertebra
exerts uneven pressure or when both adjacent vertebrae exert such
pressure on the disc. Oftentimes, disc problems lead to the
vertebrae impinging on one of the very many nerves located in the
spinal column.
[0004] One surgical method commonly utilized to correct such disc
problems is a fusion procedure where a surgeon fuses together
adjacent vertebrae in single or multiple levels. Different methods
(as well as apparatus for use in those methods) for such surgery
have been developed for performance on cervical, thoracic, or
lumbar vertebral bodies. These fusion procedures will be referred
to herein as interbody fusion or "IF." Traditional IF techniques
generally involve removing at least a portion of the troublesome
disc from the patient, adding bone graft material into the
interbody space between the vertebrae that flank the disc, and
inserting a spinal implant device into the space to hold the graft
material in place and to support the vertebrae while solid bone
mass forms therebetween. Oftentimes, the steps of inserting an
implant and bone graft material involve first packing the implant
with the bone graft material, and thereafter implanting that
construct.
[0005] While IF is a long-established technique for correcting the
aforementioned disc problems, it is one that is constantly updated.
For instance, different implants have been created to suit specific
needs, and methods involving the insertion of such implants and the
preparation of the vertebrae to receive same are constantly
evolving. One major issue that has existed and will continue to
exist is the fact that implants inserted into the disc space often
take an extended period of time to achieve permanent fusion between
the adjacent vertebrae. This leads to long recovery periods for the
patient. Certain implants also fail to achieve a degree of fusion
that permanently eliminates flexion, extension, and axial movement
between the two adjacent vertebrae. This may allow for the initial
fusion created by the implant to wear down in certain aspects,
which in turn allows for future discomfort to the patient and
potentially follow-up surgical procedures.
[0006] Thus, there exists a need for a spinal implant, method of
using the implant, and related instrumentation for such method that
improves upon these shortcomings.
BRIEF SUMMARY OF THE INVENTION
[0007] A first aspect of the present invention is a surgical
instrument for inserting a spinal implant in the intervertebral
disc space between two adjacent vertebrae and an anchor engageable
with the implant and an adjacent vertebra comprising an engagement
portion including a superior surface, an inferior surface, a distal
engagement surface for interfacing with the implant, and a track on
at least one of the superior and inferior surfaces for slidably
translating the anchor toward the engagement surface, and a handle
portion connected to the engagement portion having a proximal
surface for impaction.
[0008] In accordance with certain embodiments of this first aspect,
the instrument may include a rod extending from the engagement
surface. The rod may be threadably engageable with a corresponding
aperture in the implant. The handle portion may include a knob
connected with the rod for threading the rod into the aperture in
the implant. The engagement surface may be curved according to the
contour of the implant. The instrument may further include a
shoulder extending from at least one of the superior and inferior
surfaces of the engagement portion. The instrument may further
include connection features on lateral sides of the engagement
portion for connection to additional surgical instruments. The
connection features may include channels. The track may be embedded
within the surface. The track may include a first track on the
superior surface and a second track on the inferior surface. The
first and second tracks may each include a pair of tracks on the
respective surface.
[0009] A second aspect of the present invention is a kit of
surgical instruments for inserting a spinal implant in the
intervertebral disc space between two adjacent vertebrae and an
anchor engageable with the implant and an adjacent vertebra
comprising an inserter having an engagement portion and a handle
portion, the engagement portion including a superior surface, an
inferior surface, a distal engagement surface for interfacing with
the implant, and a track on at least one of the superior and
inferior surfaces for slidably translating the anchor toward the
engagement surface, and the handle portion connected to the
engagement portion and having a proximal surface for impaction, and
a tamp slidably engageable with the inserter in contact with the
anchor to force the anchor into engagement with the implant and the
adjacent vertebra.
[0010] In accordance with certain embodiments of this second
aspect, the kit may further include a cutter slidably engageable
with the inserter for piercing an adjacent vertebra, the cutter
having at least one blade edge for cutting bone. The tamp and the
cutter may be slidably mountable within channels on the inserter.
The tamp and the cutter may be slidably mountable within the track.
The tamp and the cutter may each include a proximal surface for
impaction. The tamp may include at least one blade edge for cutting
bone.
[0011] A third aspect of the present invention is a method of
inserting an implant in the intervertebral disc space between two
adjacent vertebrae and an anchor engageable with the implant and an
adjacent vertebra comprising the steps of attaching a distal end of
an inserter to the implant, inserting the implant into the disc
space by manipulating the inserter, inserting an anchor into
engagement with the implant and the adjacent vertebra, and sliding
a tamp along the inserter in contact with the anchor to force the
anchor into engagement with the implant and the adjacent
vertebra.
[0012] In accordance with certain embodiments of this third aspect,
the step of sliding the tamp may include impacting a proximal end
of the tamp. The method may further include the step of cutting an
entryway into the adjacent vertebra for the anchor by sliding a
cutter along the inserter and piercing the opposing adjacent
vertebra. The method may further include the step of cutting an
entryway into the adjacent vertebra for the anchor by sliding the
tamp along the inserter and piercing the opposing adjacent
vertebra. The step of attaching may include securing the implant to
the distal end of the inserter by inserting a rod of the inserter
into an aperture of the implant. The step of inserting the rod may
include screwing a threaded portion of the rod into a threaded
portion of the aperture. The step of screwing may include
tightening the threaded rod by way of a knob disposed at a handle
of the inserter. The step of inserting the implant may include
impacting a proximal end of the inserter. The step of inserting the
anchor may include locking the anchor to the implant to prevent
migration and backout of the anchor with respect to the implant.
The step of inserting the anchor may include locking the anchor to
the adjacent vertebra to prevent migration and backout of the
anchor with respect to the adjacent vertebra. The anchor may
prevent axial movement an axis of the spine between the implant and
the adjacent vertebra along. The anchor may prevent torsional
movement between the implant and the adjacent vertebra.
[0013] In accordance with additional embodiments of the third
aspect, the method may further include the steps of inserting a
second anchor into engagement with the implant and the opposing
adjacent vertebra, and sliding the tamp along the inserter in
contact with second anchor to force the anchor into engagement with
the implant and the opposing adjacent vertebra. The method may
further include cutting an entryway into the opposing adjacent
vertebra for the second anchor by sliding a cutter along the
inserter and piercing the opposing adjacent vertebra. The method
may further include inserting third and fourth anchors into
engagement with the implant and adjacent vertebrae such that two
anchors are engaged at a superior surface of the implant and two
anchors are engaged at an inferior surface of the implant. The
method may further include the step of preparing the intervertebral
disc space by removing at least a portion of the intervertebral
disc. The method may further include packing a chamber of the
implant with graft material. The method may further include the
steps of providing a kit of differently sized and shaped implants
and anchors, and selecting an implant and an anchor according to
the anatomy of the patient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of an implant and an anchor
connected to an insertion instrument having an inserter and two
tamps in accordance with a first embodiment of the present
invention.
[0015] FIG. 2 is a perspective view of the inserter and a tamp
shown in FIG. 1.
[0016] FIGS. 3A and 3B are top plan views of the proximal and
distal ends, respectively, of the inserter and tamp shown in FIG.
1.
[0017] FIG. 4 is a perspective view of the distal end of a pilot
cutter in accordance with the first embodiment.
[0018] FIG. 5 is a perspective view of the distal end of the tamp
shown in FIG. 1.
[0019] FIG. 6 is a perspective view of the implant and two anchors
shown in FIG. 1 inserted into an intervertebral disc space between
two adjacent vertebrae.
[0020] FIG. 7 is a perspective view of the implant and two anchors
shown in FIG. 6.
[0021] FIG. 8 is a side elevational view of the anchor shown in
FIG. 1.
[0022] FIG. 9 is a perspective view of an implant connected to an
inserter in accordance with a second embodiment of the present
invention.
[0023] FIG. 10 is a top plan view of the inserter shown in FIG.
9.
[0024] FIG. 11 is a perspective view of the distal end of the
inserter shown in FIG. 9.
[0025] FIG. 12 is a perspective view of a distal end of a tamp in
accordance with the second embodiment.
[0026] FIG. 13 is a perspective view of the implant attached to the
inserter shown in FIG. 9 inserted into an intervertebral disc space
between two adjacent vertebrae.
[0027] FIG. 14 is a perspective view of an anchor inserted in the
intervertebral disc space by the inserter shown in FIG. 9 and the
tamp shown in FIG. 12.
[0028] FIG. 15 is a perspective view of the implant shown in FIG.
13 and four anchors inserted into an intervertebral disc space
between two adjacent vertebrae.
[0029] FIG. 16 is a perspective view of the implant and two anchors
shown in FIG. 15.
DETAILED DESCRIPTION
[0030] In accordance with a first embodiment of the present
invention, a set of instruments is shown in FIGS. 1-5 that are
configured for installation of an implant 100 and anchors 130, 140
shown alone in FIGS. 7 and 8. The instruments include an inserter
200, a pilot cutter 300, and an anchor tamp 400.
[0031] By way of reference to certain aspects of the
below-described instruments, FIGS. 7 and 8 show implant 100 and
anchors 130, 140, which are described more thoroughly in United
States Non-Provisional patent application Ser. Nos. 12/640,816,
12/640,860, and 12/640,892, the disclosure of which is hereby
incorporated by reference herein in its entirety. Implant 100
includes, for example, a spacer 106 and a jacket 108 disposed
thereabout to provide added strength and support for implant 100.
Spacer 106 includes chambers 107a, 107b that can be packed with
graft material. Anchor 130 is essentially identical to anchor 140
and is configured to engage the vertebral bodies adjacent the
intervertebral disc space in which implant 100 is inserted. In the
implanted position, anchors 130, 140 are disposed on opposite sides
of the spacer 100. Implant 100 includes interconnection features
110, 112 that extend across spacer 106 and jacket 108 to mate with
interconnection portions 132, 142 of anchors 130, 140,
respectively. Interconnection portions 132, 142 preferably transmit
tension, compression, shear, torsion, and bending loads between
anchors 130, 140 and implant 100, so that spinal loads are
distributed from one vertebra to another through anchors 130, 140
and across leading and trailing portions of jacket 108. Anchor 130
is generally elongate with a leading end 134 and a trailing end 136
opposite therefrom, with interconnection portion 132 extending
therebetween. Interconnection portion 132 is shaped and sized to
mate with interconnection feature 110 of implant 100, so as to
slidably connect anchor 130 with implant 100. Anchor 130 further
includes a fixation portion 138 configured as a plate extending
between leading and trailing ends 134, 136. Anchor 130 also
includes legs 135, 137 extending generally perpendicularly between
interconnection portion 132 and fixation portion 138. Leg 135,
which is disposed toward leading end 134 of anchor 130, includes a
cutting edge 139 and a piercing tip 133 capable of cutting through
bone.
[0032] Inserter 200 is capable of attaching securely to implant 100
and placing it into the intervertebral disc space, delivering the
anchors 130, 140, and guiding pilot cutter 300 and anchor tamp 400.
Inserter 200 is an elongate instrument that includes a body 214
having a proximal end 202 (best shown in FIG. 3A) and a distal end
204. At distal end 204, inserter 200 includes a concavely-curved
surface 206 that is preferably shaped to match the curvature of
implant 100. Surface 206 can be planar or otherwise shaped to more
accurately match the contours of the implant with which it is
utilized. A smooth pin 210 extends from surface 206 that interfaces
with an appropriately sized aperture 102 on implant 100 to locate
and couple implant 100 to inserter 200. Pin 210 is preferably
dimensioned to correspond with aperture 102 such that a tight fit
is formed therebetween. A threaded rod 212 is disposed between
proximal end 202 and distal end 204 and runs through body 214 of
inserter 200. Rod 212 is engaged with a threaded aperture 104 of
implant 100 and is controlled by a thumb wheel 216 (best shown in
FIG. 3A) located at proximal end 202 of inserter 200 that allows
the user to tighten implant 100 to face 208 of inserter 200, thus
securing implant 100 rigidly in all six degrees of freedom with
respect to inserter 200.
[0033] As shown in FIG. 3A, proximal end 202 of inserter 200
includes a handle 208 and a large face 226 capable of withstanding
blows from a mallet to facilitate insertion of implant 100 when
impaction is required. A surgeon may grasp and control the
instrument at handle 208 without his/her hand or fingers coming
into contact with soft tissues of the cervical spine during use of
inserter 200.
[0034] Inserter 200 has a superior longitudinal channel 218 and an
inferior longitudinal channel 220 located on superior surface 228
and inferior surface 230, respectively, of inserter 200 and being
capable of containing, aligning, and slidably delivering anchors
130, 140 to engage with implant 100 and the adjacent vertebral
bodies once implant 100 is inserted into the disc space. Inserter
200 also includes flanges 222, 224 on a lateral side of inserter
200 that define a channel 223 capable of slidably mating with
conforming features on cutter 300 and tamp 400 to allow for
translation along a longitudinal axis of inserter 200. Similar
flanges and a channel are disposed on the opposed lateral side of
inserter 200.
[0035] Also at its distal end 204, inserter 200 includes a pair of
shoulders 232a, 232b on superior surface 228 and a similar pair of
shoulders 234a, 234b on inferior surface 230. Shoulders 232a, 232b,
234a, 234b are configured to engage with cutter 300 and tamp 400 to
provide a stop for preventing such instruments and implant 100 from
advancing too far into the intervertebral space or adjacent
vertebral bodies. Each pair of shoulders is disposed on the
respective superior and inferior surfaces 228, 230 so as not to
cover or otherwise obstruct longitudinal channels 218, 220. Each
shoulder also has a height adjacent channels 218, 220 that
corresponds with the dimensions of anchors 130, 140 such that
anchors 130, 140 may pass shoulders 232a, 232b, 234a, 234b without
coming into contact with same.
[0036] Inserter 200 is preferably at least somewhat symmetrical
about a horizontal plane parallel to and extending between superior
and inferior surfaces 228, 230 such that inserter 200 may be
utilized in the orientation depicted or in an inverted orientation.
As implant 100 possesses a similar symmetry, inserter 200 can be
connected with implant 100 in either orientation. In that regard,
it is also beneficial that aperture 102 of implant 100 be threaded
as well as threaded aperture 104 so that inserter 200 can be
properly engaged and locked to implant 100 in either orientation.
Of course, smooth pin 210 of inserter 200 can be configured to
engage a aperture, threaded or not, to aid in securing and
orienting implant 100 with respect to inserter 200. Inserter 200 is
also preferably at least somewhat symmetrical about a vertical
plane that bisects superior and inferior surfaces 228, 230.
[0037] Inserter 200 is preferably constructed of metal, and may
include two or more metals. For example, body 214 may be
constructed of stainless steel while handle 208 is constructed of
titanium, which may be color anodized. Of course any other material
suitable for use during surgery may be employed in the construction
of inserter 200. Preferably, the materials utilized in the
construction of inserter 200 are capable of being sterilized
multiple times, so that the inserter may be utilized in multiple
surgeries/procedures.
[0038] Shown in FIG. 4, cutter 300 is an elongate instrument
preferably constructed of stainless steel, and is primarily used
for cutting an initial pathway through the vertebral bodies,
through which anchors 130, 140 can be led. In particular, cutter
300 is configured to cut a starter channel with minimal force,
thereby reducing the total amount of trauma to the vertebral bodies
as anchors 130, 140 continue to penetrate the bone. On a distal end
306, cutter 300 includes a blade surface 304 and a trocar-type
needle tip 302 extending distally from a front face 314. Additional
blades, such a blade 316, can be positioned about blade surface 304
and needle tip 302 as necessary to aid in cutting the vertebral
bodies. Multiple blade surfaces or needle tips may also be included
as necessary according to the construction of the associated
implant and anchors. Blade surface 304 is similar in geometry to
cutting edge 139 of anchor 130, minimizing the total force required
to insert anchor 130. Needle tip 302 is also geometrically similar
to piercing tip 133.
[0039] Cutter 300 includes wings 308, 310 extending from a main
body 312 that engage with channels, such as channel 223, in
inserter 200 to allow for sliding engagement between cutter 300 and
inserter 200 to control the path of the cutter 300 during
insertion. Front face 314 is configured to abut shoulders 232a,
232b or 234a, 234b during use of cutter 300 to prevent
overextending cutter 300 into the vertebral bodies. Once mated with
inserter 200, cutter 300 may be impacted on a surface (not shown)
at its proximal end, such surface being disposed adjacent to and
preferably proximally of face 226 of proximal end of inserter 200.
Impaction of the surface at the proximal end of cutter 300 aids in
forcing blade surface 304, needle tip 302, and blade 316 into the
bone.
[0040] Cutter 300 includes a surface 318 along main body 312 that
is disposed generally parallel to superior surface 228 or inferior
surface 330 when cutter 300 is engaged with inserter 200. Handle
208 of inserter 200 may include a surface 236, as shown in FIG. 3A,
that extends above superior surface 228 (or alternatively, inferior
surface 330) such that surface 318 of cutter 300 and surface 236 of
handle 208 may be substantially coplanar when cutter 300 is engaged
with inserter 200. Thus, a surgeon may grasp the combination of
cutter 300 and inserter 200 at handle 208, and main body 312 of
cutter 300 will not protrude from handle 208, which might make
grasping the instruments awkward or uncomfortable. This
configuration also allows cutter 300 to easily translate with
respect to inserter 200 during impaction of cutter 300 while the
surgeon maintains his or her grip around handle 208.
[0041] As shown in FIG. 5, tamp 400 is an elongate, thin instrument
constructed of stainless steel, and is used primarily for the
insertion of anchors 130, 140 into the vertebral bodies. Tamp 400
includes a distal end 402 that matches the conforming geometry on
the proximal end of anchor 130, and more particularly, with respect
to the proximal portions of leg 137 and fixation portion 138. When
assembled to the inserter 200, tamp 400 engages the proximal end of
anchor 130 to controllably push anchor 130 into the vertebral body.
Distal end 402 includes a lead edge 404, a secondary edge 406, and
an angled top portion 408. Lead edge 404 and angled top portion 408
are configured to mate with leg 137 and fixed portion 138, while
secondary edge 406 is configured to mate with the proximal end of
interconnection element 132, which extends further proximally than
the other components of anchor 130. The mating surfaces between
tamp 400 and anchor 130 can be of any configuration as long as tamp
400 may push anchor 130 distally when force is exerted at a
proximal end 410 of tamp 400. Tamp 400 may conform to the mating
surfaces of anchor 130 or it may not. As described below with
respect to the second embodiment, tamp 400 may be provided with
appropriate cutting edges to operate as both a cutter and a tamp.
Of course, in such a case, the tamp would first be utilized to cut
the bone and thereafter utilized to insert the anchors in
place.
[0042] Tamp 400 includes wings 414, 416 extending from a main body
418, and wings 414, 416 engage channels, such as channel 223, in
inserter 200 in a similar manner as cutter 300. Thus, sliding
engagement is permitted between tamp 400 and inserter 200 to
control the path of tamp 400 during insertion. A front face 420 is
also included at distal end 402 of tamp 400 and is configured to
abut shoulders 232a, 232b or 234a, 234b during use of tamp 400 to
prevent overinsertion of anchors 130, 140 into the vertebral
bodies. Once mated with inserter 200, tamp 400 may be impacted
similarly to cutter 300 on an impaction surface 412 at proximal end
410, as shown in FIG. 3A. Impaction of surface 412 aids in forcing
distal end 402 of tamp 400, and accordingly, anchors 130, 140 into
the bone.
[0043] Also similar to cutter 300, tamp 400 includes a surface 422
along main body 418 that is disposed generally parallel to superior
surface 228 or inferior surface 330 when tamp 400 is engaged with
inserter 200. Surface 422 and surface 236 of handle 208 may be
substantially coplanar when tamp 400 is engaged with inserter 200.
Thus, a surgeon may grasp the combination of tamp 400 and inserter
200 at handle 208, and main body 418 will not protrude from handle
208, which might make grasping the instruments awkward or
uncomfortable. Instead, tamp 400 may easily translate with respect
to inserter 200 during impaction of tamp 400 while the surgeon
maintains his or her grip around handle 208.
[0044] A method of inserting implant 100 may begin with a surgeon
being provided with a kit of differently sized and shaped implants
and anchors and the surgeon selecting a particular implant and
corresponding anchors according to the anatomy of the patient upon
which the surgical procedure is to be performed. Selected implant
100 is then attached to distal end 204 of inserter 200. Preferably,
smooth pin 210 is inserted into aperture 102 of implant to secure
implant 100 to inserter 200 in a particular orientation. Threaded
rod 212 may also or alternatively be inserted into threaded
aperture 104 for additional attachment. Threaded rod 212 may be
screwed into aperture 104 by the surgeon actuating thumb wheel 216
disposed at handle 208. Implant 100 and inserter 200 are now
secured to one another such that manipulation of inserter 200 can
ensure proper positioning of implant within the disc space.
[0045] The intervertebral disc space is prepared by removing at
least a portion of the intervertebral disc material. This can be
done at this stage of the procedure or prior to the surgeon's
selection or attachment of implant 100. With the appropriate
portion of the disc space cleared, the surgeon aligns and inserts
implant 100 into the disc space by manipulating inserter 200,
preferably at handle 208 to allow for the area adjacent the disc
space to remain free and clear so that the procedure can be
appropriately observed. If necessary, face 226 at proximal end 202
of inserter 200 may be impacted by a surgical mallet or other
device to allow for proper insertion and position of implant 100
between the adjacent, often collapsed, vertebrae. To further aid in
fusing implant 100 to the adjacent vertebrae, one or both of
chambers 107a, 107b may be packed with bone graft material prior to
insertion of implant 100 within the disc space.
[0046] Entryways for anchors 130, 140 are then cut into the
adjacent vertebrae. While distal end 204 of inserter 200 is still
engaged to implant 100 and positioned adjacent to the disc space,
cutter 300 is slidably attached to inserter 200 with wings 308, 310
disposed in channel 223 and a channel on the opposing lateral
surface of inserter 200. Cutter 300 is advanced toward the
respective vertebra and needle tip 302, blade surface 304, and
blade 316 are used to pierce an entryway into the bone. A surgical
mallet or other device may be used to strike a proximal end of
cutter 300 protruding proximally of handle 208 to assist in
preparing the entryway in the bone. Front face 314 preferably
contacts shoulders 232a, 232b to prevent cutter from being inserted
too far into the vertebra, although it is not necessary that cutter
300 be inserted to a depth that requires contact between front face
314 and shoulders 232a, 232b. Cutter 300 is then disengaged from
the bone and inserter 200.
[0047] Anchor 130 is then loaded into longitudinal channel 218,
which can also be described as a track on superior surface 228.
Interconnection element 132 is disposed within channel 218, and
tamp 400 is slidably attached to inserter 200 proximal of anchor
130 with wings 414, 416 disposed in channel 223 and a channel on
the opposing lateral surface of inserter 200. Inserter 200 may be
alternatively configured to allow for side loading of anchor 130 so
that tamp 400 may be pre-attached to inserter 200. At least lead
edge 404, and preferably secondary edge 406, contact trailing end
136 of anchor 130. As tamp 400 is advanced toward the vertebra, it
forces anchor 130 along with it and eventually into contact with
the bone. The maintained alignment of inserter 200 with the
vertebra and the configuration of cutter 300 ensure that anchor 130
is aligned with the pre-cut entryway as it contacts the bone. Tamp
400 is further advanced to fully insert anchor 130 into the
vertebra such that interconnection element 132 of anchor 130 locks
into place within interconnection feature 110 of implant 100.
Shoulders 232a, 232b may abut front face 420 of tamp 400 during
advancement to ensure that anchor 130 is not over-inserted. Anchor
130 is eventually seated such that migration and backout are
prevented between anchor 130 with respect to both implant 100 and
the adjacent vertebra. Thus, axial and torsional movement between
implant 100 and the adjacent vertebra are prevented.
[0048] Anchor 140 may be inserted in the same manner as described
above, although with respect to inferior face 230 of inserter 200.
Cutter 300 may be used sequentially or two cutters 300 may be
utilized and employed simultaneously to cut the respective
entryways. Likewise, tamp 400 may be used first on anchor 130 and
subsequently on anchor 140, or two tamps 400 may be utilized
together, such as shown in FIG. 1. It is noted that tamp 400 and
pilot cutter 300 are generally restrained in 5 degrees of freedom
with respect to inserter 200 during insertion.
[0049] After tamp 400 is disengaged from inserter 200, threaded rod
212 is unthreaded from implant 100, again using thumb wheel 216.
Inserter 200 is then removed from the surgical site, leaving
implant 100 and anchors 130, 140 in position as shown in FIG. 6.
When implant 100 and anchors 130, 140 are implanted from an
anterior approach, as shown in FIG. 6, the leading portion of
jacket 108 is positioned in the posterior portion of the
intervertebral disc space and the trailing portion of jacket 108 is
positioned in the anterior portion of the intervertebral disc
space. In this arrangement, prosthesis implant 100 and anchors 130,
140 may replicate the strength and stiffness of the natural
anterior and posterior longitudinal ligaments to provide superior
fixation of adjacent vertebral bodies.
[0050] In accordance with a second embodiment of the present
invention, a set of instruments is shown in FIGS. 9-14 that are
configured for installation of an implant 170 and anchors 150, 160,
164, 166 shown in FIGS. 15 and 16. The instruments include an
inserter 500 and an anchor tamp 600.
[0051] With reference to certain aspects of the below-described
instruments, FIGS. 15 and 16 show implant 170 and anchors 150, 160,
164, 166, which are similar in nearly all respects to the
above-described implant 100 and anchors 130, 140, and which are
also described more thoroughly in United States Non-Provisional
patent application Ser. Nos. 12/640,816, 12/640,860, and
12/640,892. Implant 170 includes, for example, a spacer 176 and a
jacket 178 disposed thereabout. Spacer 176 includes chambers 177a,
177b, 177c that can be packed with graft material. Anchor 150 is
essentially identical to anchors 160, 164, 166 and is configured to
engage the vertebral body and implant 170. In the implanted
position, anchors 150, 164 are disposed on opposite sides of
implant 170 from anchors 160, 166. Implant 170 includes
interconnection features 180, 182, 184, 186 that extend across
spacer 176 and jacket 178 to mate with interconnection portions
152, 162, 168, 169, of anchors 150, 160, 164, 166, respectively.
Anchor 150 is generally elongate with a leading end and a trailing
end opposite therefrom, with interconnection portion 152 extending
therebetween. Interconnection portion 152 is shaped and sized to
mate with interconnection feature 180 of implant 170. Anchor 150
further includes a fixation portion 158 configured as a plate
extending between leading and trailing ends 154, 156. Anchor 150
also includes legs extending generally perpendicularly between
interconnection portion 152 and fixation portion 158. The leading
leg includes a cutting edge and a piercing tip capable of cutting
through bone.
[0052] Shown in FIGS. 9-11, inserter 500 is capable of attaching
securely to implant 170 and placing it into the intervertebral disc
space, delivering the anchors 150, 160, 164, 166, and guiding
anchor tamp 600. Inserter 500 is an elongate instrument that
includes a body 514 having a proximal end 502 and a distal end 504.
At distal end 504, inserter 500 includes a concavely-curved surface
506 that is preferably shaped to match the curvature of implant
170. Surface 506 can be planar or otherwise shaped to more
accurately match the contours of the implant with which it is
utilized. A threaded rod 512 runs through body 514 and is disposed
between proximal end 502 and distal end 504 of inserter 500. Rod
512 extends distally of surface 506, is engageable with a threaded
aperture 174 of implant 170, and is controlled by a rotatable knob
516 located at proximal end 502 of inserter 500 that allows the
user to tighten implant 170 to surface 506 of inserter 500, thus
securing implant 170 rigidly in all six degrees of freedom with
respect to inserter 500. Tabs 540a, 540b also protrude from surface
506 and engage with corresponding portions of implant 170.
[0053] Proximal end 502 of inserter 500 includes a handle 508 and a
large face 526 capable of withstanding blows from a mallet to
facilitate insertion of implant 170 when impaction is required. A
surgeon may grasp and control the instrument at handle 508 without
his/her hand or fingers coming into contact with soft tissues of
the cervical spine during use of inserter 500.
[0054] Inserter 500 has superior longitudinal channels 518, 519 and
inferior longitudinal channels 520, 521 located on superior surface
528 and inferior surface 530, respectively, of inserter 500 and
being capable of containing, aligning, and slidably delivering
anchors 150, 160, 164, 166 to engage with implant 170 and the
adjacent vertebral bodies once implant 170 is inserted into the
disc space. The pairs of channels 518, 519, 520, 521 cross on their
respective surfaces according to the orientation of the anchors
150, 160, 164, 166 with respect to implant 170. Of course, channels
518, 519, 520, 521 may be oriented with respect to their respective
surface 528, 530 at any angle with surface 506, and may be crossed,
angled, or parallel. Channels 518, 519, 520, 521 may also be angled
with respect to their respective surface 528, 530 such that their
depth extends along a direction that is perpendicular or angled or
canted with their respective surface 528, 530. As shown in FIG. 11,
channels 518, 519, 520, 521 are each angled with their respective
surface 528, 530. The angles of channels 518, 519, 520, 521
correspond with the orientation of the interconnection features of
the implant, and determine the final positioning of the anchors.
Channels 518, 519, 520, 521 are also used to guide tamp 600 when
tapping the respective anchor into implant 170 and the adjacent
vertebra. Tamp 600 accesses channels 518, 519, 520, 521 at a
proximal face 542 of distal end 504, shown more clearly in FIG.
14.
[0055] Also at its distal end 504, inserter 500 includes a post 538
on superior surface 528 and a similar post 539 on inferior surface
530. Posts 538, 539 are configured to engage with the adjacent
vertebral bodies to provide a stop for preventing over-insertion of
inserter 500. Each post 538, 539 is disposed on the respective
superior and inferior surfaces 528, 530 so as not to cover or
otherwise obstruct channels 518, 519, 520, 521.
[0056] Inserter 500 is preferably at least somewhat symmetrical
about a horizontal plane parallel to and extending between superior
and inferior surfaces 528, 530 such that inserter 500 may be
utilized in the orientation depicted or in an inverted orientation.
As implant 170 possesses a similar symmetry, inserter 500 can
beneficially be connected with implant 170 in either orientation.
Inserter 500 is also preferably at least somewhat symmetrical about
a vertical plane that bisects superior and inferior surfaces 528,
530.
[0057] Inserter 500 is preferably constructed of metal, and may
include two or more metals. For example, body 514 may be
constructed of stainless steel while handle 508 is constructed of
titanium, which may be color anodized. Of course any other material
suitable for use during surgery may be employed in the construction
of inserter 500. Preferably, the materials utilized in the
construction of inserter 500 are capable of being sterilized
multiple times, so that the inserter may be utilized in multiple
surgeries/procedures.
[0058] As shown in FIGS. 12 and 14, tamp 600 is a long instrument
constructed preferably of stainless steel, and is used primarily
for the insertion of anchors 150, 160, 164, 166 into the vertebral
bodies. Tamp 600 includes a proximal end 622 and a distal end 602
with a lead edge 604 that may or may not match the conforming
geometry on the proximal end of anchor 150. When assembled to the
inserter 500, tamp 600 engages the proximal end of anchor 150 to
controllably push anchor 150 into the vertebral body. The mating
surfaces between tamp 600 and anchor 150 can be of any
configuration as long as tamp 600 may push anchor 150 distally when
force is exerted at proximal end 622.
[0059] Tamp 600 has a profile that allows it to fit within channels
519, 520, 521, 522. Thus, sliding engagement is permitted between
tamp 600 and inserter 500 to control the path of tamp 600 during
insertion. A stop face 626 is provided that separates a cutting
portion 620 from a main body 612. Stop face 626 is configured to
abut face 542 of inserter 500 during use of tamp 600 to prevent
overinsertion of anchors 150, 160, 164, 166 into the vertebral
bodies. Once mated with inserter 500, tamp 600 may be impacted
similarly to the above described first embodiment on an impaction
surface 624 at proximal end 622, as shown in FIG. 14. Impaction of
surface 624 aids in forcing distal end 602 of tamp 600, and
accordingly, anchors 150, 160, 164, 166 into the bone.
[0060] While a cutter is not depicted with respect to the second
embodiment, it is contemplated that a cutter may be provided having
a similar construction to tamp 600 with the necessary cutting edges
and/or needle tips. Alternatively, tamp 600 may be provided with
appropriate cutting edges to operate as both a cutter and a tamp.
Of course, in such a case, the tamp would first be utilized to cut
the bone and thereafter utilized to insert the anchors in
place.
[0061] A method of inserting implant 170 is similar in nature to
the method described with respect to the first embodiment. The
method may begin with a surgeon being provided with a kit of
differently sized and shaped implants and anchors and the surgeon
selecting a particular implant and corresponding anchors according
to the anatomy of the patient upon which the surgical procedure is
to be performed. Selected implant 170 is then attached to distal
end 504 of inserter 500. Preferably, threaded rod 512 is inserted
into threaded aperture 174 to secure implant 170 to inserter 500 in
a particular orientation. Threaded rod 512 may be screwed into
aperture 174 by the surgeon actuating knob 516. Implant 170 and
inserter 500 are now secured to one another such that manipulation
of inserter 500 can ensure proper positioning of implant within the
disc space.
[0062] The intervertebral disc space is prepared by removing at
least a portion of the intervertebral disc material. This can be
done at this stage of the procedure or prior to the surgeon's
selection or attachment of implant 170. With the appropriate
portion of the disc space cleared, the surgeon aligns and inserts
implant 170 into the disc space by manipulating inserter 500,
preferably at handle 508 to allow for the area adjacent the disc
space to remain free and clear so that the procedure can be
appropriately observed. If necessary, face 526 at proximal end 502
of inserter 500 may be impacted by a surgical mallet or other
device to allow for proper insertion and position of implant 170
between the adjacent, often collapsed, vertebrae. Posts 538, 539
may contact the adjacent vertebral bodies to prevent overinsertion
of implant 170. To further aid in fusing implant 170 to the
adjacent vertebrae, one or more of chambers 177a, 177b, 177c may be
packed with bone graft material prior to insertion of implant 170
within the disc space.
[0063] At this point, a cutter or, if tamp is provided with the
appropriate blades, tamp 600 may be used to cut entryways into the
adjacent vertebrae (if so designed). This step is not necessary, as
anchors 150, 160, 164, 166 are configured to pierce the uncut
bone.
[0064] Anchor 164 is then loaded into longitudinal channel 519,
which can also be described as a track on superior surface 528. The
method of inserting an anchor according to the present invention is
herein described with respect to anchor 164, although more than one
anchor may be inserted simultaneously. Interconnection element 152
is disposed within channel 519, and tamp 600 is slidably attached
to inserter 500 proximal of anchor 164 within channel 519 as well,
with least lead edge 604 in contact with the trailing end of anchor
164. As tamp 600 is advanced toward the vertebra, it forces anchor
164 along with it and eventually into contact with the bone. Tamp
600 is further advanced to fully insert anchor 164 into the
vertebra such that the interconnection element of anchor 164 locks
into place within interconnection feature 184 of implant 170. Stop
face 626 may abut surface 542 of inserter 500 during advancement to
ensure that anchor 164 is not over-inserted. Anchor 164 is
eventually seated such that migration and backout are prevented
between anchor 164 with respect to both implant 170 and the
adjacent vertebra. Thus, axial and torsional movement between
implant 170 and the adjacent vertebra are prevented.
[0065] Anchors 150, 160, 166 may be inserted in the same manner as
described above, although with respect to different channels of
inserter 500. Tamp 600 may be used first on a one anchor and
subsequently on the others, or two or more tamps 600 may be
utilized together. It is noted that tamp 600 is generally
restrained in 5 degrees of freedom with respect to inserter 500
during insertion.
[0066] After tamp 600 is disengaged from inserter 500, threaded rod
512 is unthreaded from implant 170 using knob 516. Inserter 500 is
then removed from the surgical site, leaving implant 170 and
anchors 150, 160, 164, 166 in position as shown in FIG. 15. When
implant 170 and anchors 150, 160, 164, 166 are implanted from an
anterior approach, as shown in FIG. 15, the leading portion of
jacket 178 is positioned in the posterior portion of the
intervertebral disc space and the trailing portion of jacket 178 is
positioned in the anterior portion of the intervertebral disc
space. In this arrangement, prosthesis implant 170 and anchors 150,
160, 164, 166 may replicate the strength and stiffness of the
natural anterior and posterior longitudinal ligaments to provide
superior fixation of adjacent vertebral bodies.
[0067] The instruments according to the present invention are
preferably constructed of metal, although other types of materials
may be used that give the proper strength to the instruments. Such
materials could be hard polymeric materials or other plastics. Of
course any other material suitable for use during surgery may be
employed in the construction of any of the instruments. Preferably,
the materials utilized are capable of being sterilized multiple
times, so that the instruments may be utilized in multiple
surgeries/procedures.
[0068] Although the invention herein has been described with
reference to particular embodiments, it is to be understood that
these embodiments are merely illustrative of the principles and
applications of the present invention. It is therefore to be
understood that numerous modifications may be made to the
illustrative embodiments and that other arrangements may be devised
without departing from the spirit and scope of the present
invention as defined by the appended claims.
INDUSTRIAL APPLICABILITY
[0069] The present invention enjoys wide industrial applicability
including, but not limited to, systems and methods including
surgical instruments for implantation of intervertebral
implants.
* * * * *