Inter-cervical facet implant with implantation tool

• US 8,029,540 B2
• Filed: 05/08/2006
• Issued: 10/04/2011
• Est. Priority Date: 05/10/2005
• Status: Active Grant

• Current Assignee: Kyphon SARL (Medtronic Plc)
• Original Assignee: Kyphon SARL (Medtronic Plc)
• Inventors: Mitchell, Steven T., Winslow, Charles J., Markwart, John A.
• Primary Examiner(s): Barrett; Thomas C.
• Assistant Examiner(s): Yang; Andrew
• Application Number:
  US11/429,733
• Publication Number:
  US 20070016195A1
• Time in Patent Office: 1,975 Days
• Field of Search: 606247-249, 606/99, 606/914, 606/915, 606/70, 606/71, 606/283, 606/289, 623/17.11, 623/17.16
• US Class Current: 606/247
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/30 Joints

Abstract

Systems and method in accordance with the embodiments of the present invention can include an implant for positioning within a cervical facet joint for distracting the cervical spine, thereby increasing the area of the canals and openings through which the spinal cord and nerves must pass, and decreasing pressure on the spinal cord and/or nerve roots. The implant can be inserted laterally or posteriorly.

Claims

1. A facet joint implant adapted to be inserted in a facet joint, the implant comprising:

a. a facet joint spacer; and

b. an anchoring plate flexibly coupled to the facet joint spacer, the anchoring plate having a superior surface, an inferior surface opposite the superior surface, and opposing side surfaces extending between the superior surface and the inferior surface, and wherein a central longitudinal axis extends through the facet joint spacer and the anchoring plate,

wherein the anchoring plate includes an aperture through the superior surface adapted to receive a retractable engaging member of an implanting tool, the anchoring plate including a protrusion projecting in a direction transverse to the longitudinal axis from each side surface, each protrusion being disposed on the side surface at an elevation different than that of the superior surface of the anchoring plate so as to form a step from the superior surface, the protrusion being shaped to have a longitudinal length along the side surface greater than a height of the side surface, and being adapted to correspondingly register with a receiving slot of the implanting tool.

2. The implant of claim 1 wherein the protrusion further comprises a pair of winged protrusions along opposing side surfaces of the anchoring plate, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.

3. The implant of claim 1 wherein the anchoring plate further comprises:

a. a bone screw aperture adapted to receive a bone screw; and

b. a locking screw aperture adapted to receive a locking screw, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.

4. The implant of claim 1 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.

5. The implant of claim 1 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.

6. The implant of claim 1, wherein each protrusion is formed of a single, projecting body.

7. A facet joint implant adapted to be inserted in a facet joint, the implant comprising:

a. a facet joint spacer shaped to fit within a facet joint, the facet joint spacer having a superior surface configured to interface with a superior portion of the facet joint and having an inferior surface configured to interface with an inferior portion of the facet joint; and

b. an anchoring plate flexibly coupled to the facet joint spacer, the anchoring plate having a superior surface, an inferior surface opposite the superior surface, and opposing side surfaces extending between the superior surface and the inferior surface, and wherein a central longitudinal axis extends through the facet joint spacer and the anchoring plate, wherein the anchoring plate includes a protrusion projecting in a direction transverse to the longitudinal axis from each side surface, each protrusion being disposed on the side surface at an elevation different than that of the superior surface of the anchoring plate so as to form a step from the superior surface, the protrusion being shaped to have a longitudinal length along the side surface greater than a height of the side surface, and being adapted to correspondingly register with a receiving slot of the implanting tool.

8. The implant of claim 7 further comprising an engagement aperture adapted to receive a retractable engagement member of the implanting tool.

9. The implant of claim 8 wherein the engagement aperture is in a superior surface of the anchoring plate.

10. The implant of claim 7 wherein the protrusion further comprises a pair of winged protrusions along opposing side surfaces of the anchoring plate, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.

11. The implant of claim 7 wherein the anchoring plate further comprises:

a. a bone screw aperture adapted to receive a bone screw; and

b. a locking screw aperture adapted to receive a locking screw, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.

12. The implant of claim 7 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.

13. The implant of claim 7 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.

14. A facet joint implant adapted to be inserted into a facet joint, the implant comprising:

a. a facet joint spacer shaped to fit within a facet joint, the facet joint spacer having a superior surface configured to interface with a superior portion of the facet joint and having an inferior surface configured to interface with an inferior portion of the facet joint; and

b. an anchoring plate moveably associated with the facet joint spacer, the anchoring plate being sized and shaped to be disposed outside the facet joint when the facet joint spacer is within the facet joint, the anchoring plate being configured to be secured to a vertebral lateral mass, wherein a central longitudinal axis extends through the facet joint spacer and the anchoring plate, and wherein the anchoring plate includes

an engagement aperture adapted to receive a retractable engaging member of an implanting tool, the engagement aperture intersecting the longitudinal axis;

a bone screw aperture adapted to receive a bone screw, the bone screw aperture intersecting the longitudinal axis and being disposed between the facet joint spacer and the engagement aperture, the bone screw aperture having a relatively larger diameter; and

a locking screw aperture adapted to receive a locking screw, the locking screw aperture being displaced from the longitudinal axis and having a relatively smaller diameter, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.

15. The implant of claim 14 wherein the engagement aperture is in a superior surface of the anchoring plate.

16. The implant of claim 14 wherein the anchoring plate further comprises a side surface having a protrusion adapted to correspondingly register in a receiving slot in the implanting tool.

17. The implant of claim 14 wherein the anchoring plate further comprises a pair of winged protrusions along opposing side surfaces, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.

18. The implant of claim 14 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.

19. The implant of claim 14 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.