Low profile intervertebral implant

• US 9,005,295 B2
• Filed: 08/27/2012
• Issued: 04/14/2015
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Kueenzi, Thomas, Walsh, Ryan, Pepe, Tom, Hunziker, Markus, Koch, David
• Primary Examiner(s): Yang, Andrew
• Assistant Examiner(s): Jones, Diana S
• Application Number:
  US13/594,965
• Publication Number:
  US 20120323330A1
• Time in Patent Office: 960 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.16
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/8033 having indirect contact with screw heads, or having contact with screw heads maintained with the aid of additional components, e.g. nuts, wedges or head covers
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2002/30077 shrinkable
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30485 plastically deformable
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0066 : shrinkable
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2230/0065 : toroidal, e.g. ring-shaped, doughnut-shaped
• CPC Class Codes: A61F 2230/0073 : Quadric-shaped
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00323 : containing titanium nitride
• CPC Class Codes: A61F 2310/00359 : Bone or bony tissue

Abstract

The present invention is directed to a low profile intervertebral implant (10) for implantation in an intervertebral disc space (D) in-between adjacent vertebral bodies (V). The intervertebral implant includes a plate (40) preferably coupled to a spacer (20). The plate is preferably formed from a first material and the spacer is preferably formed from a second material, the first material being different from the second material. The plate is preferably sized and configured so that the plate does not extend beyond the perimeter of the spacer. In this manner, the plate preferably does not increase the height profile (hs) of the spacer and the plate may be implanted within the intervertebral disc space in conjunction with the spacer.

Claims

1. A low profile intervertebral implant sized and configured to be implanted between adjacent upper and lower vertebral bodies, the implant comprising:

a spacer having a first insertion end, a second end opposite the first insertion end, a first lateral end, a second lateral end opposite the first lateral end, an upper surface that faces the upper vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, a lower surface that faces the lower vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, the first lateral end defines a first recess, and the second lateral end defines a second recess;

a plate configured to be coupled to the spacer by sliding one of the plate and the spacer relative to the other of the plate and the spacer in a direction, the plate comprising a top surface, a bottom surface, a front surface that faces the spacer when the plate is coupled to the spacer, and a rear surface opposite the front surface, wherein the rear surface defines an opening of at least one through hole that is configured to receive a bone screw to secure the implant to one of the adjacent vertebral bodies, the plate further defining a first lateral portion and a second lateral portion that each protrude relative to the front surface of the plate, each of the first and second lateral portions are configured to be inserted into the first and second recesses, respectively, to couple the plate to the spacer; and

at least one cam configured to secure the plate to the spacer when the plate is coupled to the spacer, the at least one cam coupled to at least one of the plate and the spacer such that an entirety of the at least one cam is spaced from an entirety of each of the at least one through holes, and the at least one cam is rotatable with respect to the plate from a first position in which the at least one cam prevents the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction, to a second position in which the at least one cam does not prevent the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction.

2. The implant of claim 1, wherein the recesses in the lateral ends of the spacer are formed centrally within the spacer.

3. The implant of claim 1, wherein the protruding first and second lateral portions comprise two or more substantially rectangular projections.

4. The implant of claim 1, wherein the spacer is secured to the plate using one or more screws threaded through one or more holes in the spacer and the plate.

5. The implant of claim 1, wherein a portion of each of the first and second recesses extends from the upper surface to the lower surface of the spacer.

6. The implant of claim 1, wherein the upper surface of the spacer is coplanar with the top surface of the plate and the lower surface of the spacer is coplanar with the bottom surface of the plate.

7. The implant of claim 1, wherein the plate is coupled to the spacer by unidirectionally sliding the protruding first and second lateral portions into the first and second recesses.

8. The implant of claim 1, wherein the plate is configured to be coupled to the spacer by a press-fit arrangement.

9. The implant of claim 1, wherein the first and second recesses and the protruding first and second lateral portions are tapered.

10. The implant of claim 1, wherein the protruding first and second lateral portions are sized and configured to flex across the spacer and to substantially fit inside the first and second recesses, respectively.

11. The implant of claim 1, wherein the upper surface of the spacer comprises a series of teeth.

12. The implant of claim 1, wherein the spacer comprises one or more channels configured to receive bone graft material.

13. The implant of claim 12, wherein the one or more channels extend through the spacer from the upper surface to the lower surface of the spacer.

14. The implant of claim 1, wherein the plate is formed from a first material and the spacer is formed from a second material, the first material being different from the second material.

15. The implant of claim 14, wherein the first material is a metallic material and the second material is non-metallic.

16. The implant of claim 1, wherein the plate has a height H_p measured from the top surface to the bottom surface, the second end of the spacer has a height H_s measured from the upper surface to the lower surface, the height H_p of the plate being equal to or less than the height of the spacer H_s so that the plate does not increase a height profile of the spacer when the plate is coupled to the spacer.

17. The implant of claim 1, wherein the protruding first and second lateral portions extend from the upper surface to the lower surface of the plate.

18. The implant of claim 1, wherein the at least one cam is coupled to either or both of the top surface and the bottom surface of the plate.

19. An intervertebral implant configured to be implanted between an upper vertebral body and a lower vertebral body, the implant comprising:

a spacer including a first insertion end, a second end opposite the first insertion end, a first lateral end, a second lateral end opposite the first lateral end, an upper surface that faces the upper vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, a lower surface that faces the lower vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, the spacer defining a recess that extends into the first lateral end;

a plate configured to be coupled to the spacer by sliding one of the plate and the spacer relative to the other of the plate and the spacer in a first direction, the plate including a top surface, a bottom surface, a front surface that faces the spacer in a second direction when the plate is coupled to the spacer, and a rear surface opposite the front surface in a third direction opposite the second direction, the rear surface defining an opening of at least one through hole configured to receive a bone screw, the plate further including a projection spaced from the front surface in the second direction; and

a cam configured to secure the plate to the spacer when the plate is coupled to the spacer, the cam configured to be coupled to at least one of the plate and the spacer such that the cam is offset with respect to each of the at least one through holes;

wherein the projection is configured to be inserted into the recess to couple the plate to the spacer, and when the plate is coupled to the spacer a portion of the spacer is positioned between the front surface and the projection with respect to the second direction.

20. The implant of claim 19, wherein the recess is a first recess, the projection is a first projection, the gap is a first gap, the spacer includes a second recess that extends into the second lateral end, the plate includes a second projection spaced from the front surface in the second direction such that a second gap is defined between the front surface and the second projection.

21. The implant of claim 20, wherein the second projection is configured to be inserted into the second recess to couple the plate to the spacer, and when the plate is coupled to the spacer a portion of the spacer is positioned within the second gap between the front surface and the second projection.

22. The implant of claim 19, wherein the recess extends into the upper surface and terminates within the spacer between the upper surface and the lower surface.

23. The implant of claim 19, wherein the plate has a height H_p measured from the top surface to the bottom surface, the second end of the spacer has a height H_s measured from the upper surface to the lower surface, the height H_p of the plate being equal to or less than the height of the spacer H_s so that the plate does not increase a height profile of the spacer when the plate is coupled to the spacer.

24. The implant of claim 19, wherein the cam is rotatable with respect to the plate from a first position in which the cam prevents the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction, to a second position in which the cam does not prevent the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction.

25. The implant of claim 24, wherein the cam is coupled to either or both of the top surface and the bottom surface of the plate.

26. An intervertebral implant configured to be implanted between an upper vertebral body and a lower vertebral body, the implant comprising:

a spacer including a first insertion end, a second end opposite the first insertion end, a first lateral end, a second lateral end opposite the first lateral end, an upper surface that faces the upper vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, a lower surface that faces the lower vertebral body when the intervertebral implant is implanted between the upper and lower vertebral bodies, the spacer defining a recess that extends into the first lateral end;

a plate configured to be coupled to the spacer by sliding one of the plate and the spacer relative to the other of the plate and the spacer in a first direction, the plate including a top surface, a bottom surface, a front surface that faces the spacer in a second direction when the plate is coupled to the spacer, and a rear surface opposite the front surface in a third direction opposite the second direction, the rear surface defining an opening of at least one through hole configured to receive a bone screw, the plate further including a projection spaced from the front surface in the second direction; and

a cam configured to secure the plate to the spacer when the plate is coupled to the spacer, such that the cam is rotatable with respect to the plate from a first position in which the cam prevents the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction, to a second position in which the cam does not prevent the one of the plate and the spacer from sliding completely past the other of the plate and the spacer in the direction;

wherein the projection is configured to be inserted into the recess to couple the plate to the spacer, and when the plate is coupled to the spacer a portion of the spacer is positioned between the front surface and the projection with respect to the second direction.