Method and apparatus for spinal facet fusion

• US 20090036927A1
• Filed: 05/22/2008
• Published: 02/05/2009
• Est. Priority Date: 05/22/2007
• Status: Active Grant

• Current Assignee: VG Innovations LLC
• Original Assignee: VG Innovations LLC
• Inventors: Vestgaarden, Tov
• Granted Patent: US 8,162,981 B2
• Time in Patent Office: Days
• US Class Current: 606/247
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61F 2/4405 for apophyseal or facet joints, i.e. between adjacent spinous or transverse processes devices implanted between spinous or transverse processes A61B17/7062
• CPC Class Codes: A61F 2002/30622 Implant for fusing a joint or bone material

Abstract

A spinal facet fusion implant comprising:

• • an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile characterized by a primary axis and a secondary axis; and
  • at least one stabilizer extending radially outwardly from the elongated body in the secondary axis;
  • wherein the elongated body has a length along the primary axis which is less than the combined width of the spinal facets making up a facet joint;
  • and further wherein the at least one stabilizer has a width which is sized to make a press fit into the gap between the spinal facets making up a facet joint.

Claims

1. A spinal facet fusion implant comprising:

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile characterized by a primary axis and a secondary axis; and

at least one stabilizer extending radially outwardly from the elongated body in the secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the spinal facets making up a facet joint;

and further wherein the at least one stabilizer has a width which is sized to make a press fit into the gap between the spinal facets making up a facet joint.

2. A spinal facet fusion implant according to claim 1 wherein the elongated body is chamfered at its distal end.

3. A spinal facet fusion implant according to claim 1 wherein the elongated body comprises at least one barb on its outer surface, wherein the barb is configured to permit axial insertion in the distal direction and inhibit axial retraction in the proximal direction.

4. A spinal facet fusion implant according to claim 1 wherein the elongated body is substantially solid.

5. A spinal facet fusion implant according to claim 4 wherein the elongated body includes at least one opening therein to permit bone in-growth.

6. A spinal facet fusion implant according to claim 5 wherein the at least one opening comprises a cross-bore.

7. A spinal facet fusion implant according to claim 5 wherein the at least one opening comprises a blind hole.

8. A spinal facet fusion implant according to claim 5 wherein the at least one opening is filled with a bone growth promoter.

9. A spinal facet fusion implant according to claim 1 wherein the elongated body is substantially hollow.

10. A spinal facet fusion implant according to claim 9 wherein the elongated body includes at least one opening therein to permit bone in-growth.

11. A spinal facet fusion implant according to claim 10 wherein the at least one opening comprises a cross-bore.

12. A spinal facet fusion implant according to claim 10 wherein the at least one opening comprises a blind hole.

13. A spinal facet fusion implant according to claim 10 wherein the at least one opening is filled with a bone growth promoter.

14. A spinal facet fusion implant according to claim 1 wherein the elongated body comprises at least one surface groove.

15. A spinal facet fusion implant according to claim 14 wherein the surface groove extends parallel to the longitudinal axis.

16. A spinal facet fusion implant according to claim 14 wherein the surface groove extends perpendicular to the longitudinal axis.

17. A spinal facet fusion implant according to claim 14 wherein the surface groove extends transverse to the longitudinal axis.

18. A spinal facet fusion implant according to claim 1 wherein the length of the primary axis is greater than the length of the secondary axis.

19. A spinal facet fusion implant according to claim 1 wherein the length of the secondary axis is greater than the length of the primary axis.

20. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is non-circular.

21. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is rectangular.

22. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is rounded rectangular.

23. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is ovoid.

24. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is triangular.

25. A spinal facet fusion implant according to claim 1 wherein the cross-sectional profile is circular.

26. A spinal facet fusion implant according to claim 1 wherein the at least one stabilizer extends upwardly from the elongated body.

27. A spinal facet fusion implant according to claim 1 wherein the at least one stabilizer extends downwardly from the elongated body.

28. A spinal facet fusion implant according to claim 1 wherein the fusion device comprises a pair of stabilizers.

29. A spinal facet fusion implant according to claim 28 wherein the pair of stabilizers are diametrically opposed from one another.

30. A spinal facet fusion implant according to claim 1 wherein the spinal facet fusion implant further comprises a fixation device for securing the spinal facet fusion implant in the facet joint.

31. A spinal facet fusion implant according to claim 30 wherein the fixation device comprises a screw.

32. A method for fusing a spinal facet joint, the method comprising the steps of:

providing a spinal facet fusion implant comprising;

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile characterized by a primary axis and a secondary axis; and

at least one stabilizer extending radially outwardly from the elongated body in the secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the spinal facets making up a facet joint;

and further wherein the at least one stabilizer has a width which is sized to make a press fit into the gap between the spinal facets making up a facet joint;

deploying the spinal facet fusion implant in the facet joint so that the elongated body is simultaneously positioned within both of the facets of the facet joint and the at least one stabilizer is positioned within the gap between the spinal facets; and

maintaining the spinal facet fusion implant in this position while fusion occurs.

33. A method according to claim 32 wherein the spinal facet fusion implant is installed in a hole which is preformed in the two spinal facets making up the facet joint.

34. A method according to claim 32 wherein the spinal facet fusion implant is installed into the virgin bone of the spinal facets.

35. A spinal facet fusion implant comprising:

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile which is characterized by a primary axis and a secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the spinal facets making up a facet joint;

and further wherein the cross-sectional profile is non-circular.

36. A method for fusing a spinal facet joint, the method comprising the steps of:

providing a spinal facet fusion implant comprising;

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile which is characterized by a primary axis and a secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the spinal facets making up a facet joint;

and further wherein the cross-sectional profile is non-circular;

deploying the spinal facet fusion implant in the facet joint so that the elongated body is simultaneously positioned within both of the facets of the facet joint; and

maintaining the spinal facet fusion implant in this position while fusion occurs.

37. A joint fusion implant comprising:

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile characterized by a primary axis and a secondary axis; and

at least one stabilizer extending radially outwardly from the elongated body in the secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the bones making up the joint;

and further wherein the at least one stabilizer has a width which is sized to make a press fit into the gap between the bones making up the joint.

38. A method for fusing a joint, the method comprising the steps of:

providing a fusion implant comprising;

an elongated body having a distal end, a proximal end and a longitudinal axis extending between the distal end and the proximal end, the elongated body having a cross-sectional profile characterized by a primary axis and a secondary axis; and

at least one stabilizer extending radially outwardly from the elongated body in the secondary axis;

wherein the elongated body has a length along the primary axis which is less than the combined width of the bones making up the joint;

and further wherein the at least one stabilizer has a width which is sized to make a press fit into the gap between the bones making up the joint;

deploying the fusion implant in the joint so that the elongated body is simultaneously positioned within both of the bones of the joint and the at least one stabilizer is positioned within the gap between the bones; and

maintaining the fusion implant in this position while fusion occurs.