Facet interference cage

Patent metadata

Field	Value
Publication number	US-9918743-B2
Application number	US-201213465508-A
Country	US
Kind code	B2
Filing date	May 7, 2012
Priority date	May 10, 2011
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

An implant includes a body sized and shaped for insertion into a facet joint, the implant including a first bone fixation element receiving opening extending through a portion thereof along a first axis oriented so that, when the implant is received within a facet joint in a desired configuration, a bone fixation element inserted into the first bone fixation element receiving opening will extend into a first one of the vertebra forming the facet joint.

First claim

What is claimed:

1. A facet joint implant sized and shaped for insertion into a facet joint of the human spine, the facet joint implant comprising:
a proximal end surface, and a distal end surface opposite the proximal end surface along a longitudinal direction;
a first lateral surface, and a second lateral surface opposite the first lateral surface along a second direction perpendicular to the longitudinal direction, wherein the proximal and distal end surfaces and the first and second lateral surfaces define outermost peripheral surfaces of the implant;
a first bone-engagement surface, and a second bone-engagement surface opposite the first bone-engagement surface along a third direction that is perpendicular to each of the longitudinal direction and the second direction, wherein the facet joint implant has a first height between the second bone-engagement surface and the first bone-engagement surface proximate the proximal end surface that is greater than a second height between the second and the first bone-engagement surfaces proximal the distal end surface, the facet joint implant having a cut out extending from the distal end surface toward the proximal end surface and from the first bone-engagement surface to the second bone-engagement surface such that the cut out extends through the first and second bone-engagement surfaces, the cut out defined by first and second inner lateral walls spaced from one another along the second direction such that the first inner lateral wall is disposed between the first lateral surface and the second inner lateral wall, the cut out further defined by a back wall connected between the first and second inner lateral walls such that the facet joint implant defines 1) a first distal portion section that is located between the first lateral surface and the first inner lateral wall, and 2) a second distal portion section that is located between the second lateral surface and the second inner lateral wall, wherein each of the first and second distal portion sections define a respective opening that extends from the first bone-engagement surface to the second bone-engagement surface to promote bony growth;
a central opening extending through the facet joint implant along the longitudinal direction from the proximal end surface through the back wall of the cut out, the central opening sized and configured to accept a guidewire for insertion into a facet joint, wherein the central opening extends along a longitudinal axis;
a first bone fixation element hole extending from the proximal end surface and through the facet joint implant, the first bone fixation element hole overlapping with the central opening, wherein the first bone fixation element hole defines a first angle with respect to the longitudinal axis, the first angle being between 10° and 45°; and a second bone fixation element hole extending from the proximal end surface and through the facet joint implant, the second bone fixation element hole overlapping with the central opening, wherein the second bone fixation element hole defines a second angle with respect to the longitudinal axis, the second angle being between 10° and 45°.

2. The facet joint implant of claim 1 , further comprising at least one rib that extends out from the first bone-engagement surface of the first distal portion section and that is elongate in a direction that extends from the proximal end surface to the distal end surface.

3. The facet joint implant of claim 1 , further comprising at least one rib extending out from the second bone-engagement surface of the first distal portion section and that is elongate in a direction that extends from the proximal end surface to the distal end surface.

4. The facet joint implant of claim 1 , further comprising at least one rib that extends out from the first bone-engagement surface of the second distal portion section and that is elongate in a direction that extends from the proximal end surface to the distal end surface.

5. The facet joint implant of claim 1 , further comprising at least one rib that extends out from the second bone-engagement surface of the second distal portion section and that is elongate in a direction that extends from the proximal end surface to the distal end surface.

6. The facet joint implant of claim 1 , further comprising at least one rib that extends out from each of the first and second bone-engagement surfaces of each of the first and second distal portion sections, wherein each rib is elongate in a direction that extends from the proximal end surface to the distal end surface.

7. The facet joint implant of claim 1 wherein the facet joint implant is in the form of a tapered wedge-shape from the proximal end surface to the distal end surface.

8. The facet joint implant of claim 7 wherein the distal end surface has a blunt profile.

9. The facet joint implant of claim 1 wherein the first and second lateral surfaces each have a recess located adjacent the proximal end surface and each recess has a means for engaging an insertion tool defining an axis of rotation about which the facet joint implant can pivot relative to the insertion tool.

10. The facet joint implant of claim 1 wherein the first bone fixation element hole is threaded.

11. The facet joint implant of claim 1 wherein the first and second bone fixation element holes are threaded.

12. The facet joint implant of claim 1 wherein each of the first and second lateral surfaces of the facet joint implant when traced from the second end toward the first end curves in a convex-shaped arc and then in a concave-shaped arc.

13. The facet joint implant of claim 12 wherein the transition from the convex-shaped arc to the concave-shaped arc for the first lateral surface is located past the opening in the first distal portion.

14. The facet joint implant of claim 13 wherein the transition from the convex-shaped arc to the concave-shaped arc for the second lateral surface is located past the opening in the second distal portion.

15. The facet joint implant of claim 14 wherein the first and second bone-engagement surfaces of each of the first and second distal portions have a plurality of ribs that extend outward therefrom and are elongate along a direction that extends from the proximal end to the distal end.

16. The facet joint implant of claim 15 wherein each of the ribs has a plurality of teeth extending therefrom.

17. The facet joint implant according to claim 1 , wherein the first and second distal portion sections terminate at first and second free ends, respectively, defined at the distal end surface.

18. An implant sized and shaped for insertion into a facet joint of the human spine, the implant comprising:
a proximal end surface and a distal end surface, the proximal and distal end surfaces spaced from one another along a longitudinal direction;
a first outer lateral surface and a second outer lateral surface, the first and second outer lateral surfaces spaced from one another along a second direction, perpendicular to the longitudinal direction, wherein the proximal and distal end surfaces and the first and second outer lateral surfaces define outermost peripheral surfaces of the implant;
a first bone-engagement surface and a second bone-engagement surface, the first and second bone-engagement surfaces spaced from one another along a third direction, perpendicular to both the longitudinal and second directions;
a first inner lateral surface, and a second inner lateral surface that faces the first inner lateral surface so as to define a cut out therebetween that extends f

Assignees

• Pavlov Paul
• Overes Tom
• Frigg Robert
• Lindenmann Philippe
• Depuy Synthes Products Inc

Inventors

• Pavlov Paul
• Overes Tom
• Frigg Robert
• Lindenmann Philippe

Classifications

• A61F2002/30028

  differing in tissue ingrowth capacity, e.g. made from both ingrowth-promoting and ingrowth-preventing parts · CPC title

• A61F2002/3054

  about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions · CPC title

• A61F2002/30904

  serrated profile, i.e. saw-toothed · CPC title

• A61F2002/30787

  inclined obliquely with respect to each other · CPC title

• A61B17/70 Primary

  Spinal positioners or stabilisers, e.g. stabilisers comprising fluid filler in an implant · CPC title