Implant system, method, and instrument for augmentation or reconstruction of intervertebral disc
View Patent ↗An augmentation instrument for attaching a retaining device to a vertebral endplate comprises a drive housing having a distal end portion, a drive mechanism extending through the drive housing and including a flexible shaft portion, and an attachment mechanism at the distal end portion of the drive housing. The attachment mechanism is adapted for coupling to the retaining device.
1. A system for maintaining a nucleus prosthesis within an annulus having a defect, the system comprising:
a first blocking plate for preventing migration of the nucleus prosthesis through the defect in the annulus, the first blocking plate sized to be positioned substantially within an intervertebral disc space defined by a pair of adjacent vertebral endplates, the first blocking plate having a height less than a distance between the adjacent vertebral endplates but greater than half of the distance between the adjacent vertebral endplates such that the first blocking plate prevents migration of the nucleus prosthesis through the defect in the annulus without limiting the natural flexion and extension of the adjacent vertebral endplates, the first blocking plate comprising:
a substantially planar retaining face,
a substantially planar mounting face extending substantially perpendicular to the retaining face for engagement with a single one of the adjacent vertebral endplates, and
an aperture extending through the first blocking plate and through a portion of the mounting face,
wherein the first blocking plate comprises a rigid, non-resorbable biocompatible material;
a fastener sized and shaped for extending through the aperture in the first blocking plate and into the single one of the adjacent vertebral endplates to securely attach the first blocking plate to the single one of the adjacent vertebral endplates; and
an annular plug sized and shaped for positioning between the nucleus prosthesis and the first blocking plate at least partially within the defect in the annulus.
2. The system of claim 1 , wherein the annular plug is attached to the first blocking plate.
3. The system of claim 2 , wherein the annular plug is molded to the first blocking plate.
4. The system of claim 2 , wherein the annular plug is attached to the first blocking plate with a dovetail joint.
5. The system of claim 1 , wherein the annular plug is formed of a resilient material.
6. The system of claim 5 , wherein the resilient material is non-resorbable.
7. The system of claim 1 , wherein the annular plug is formed from a natural tissue.
8. The system of claim 7 , wherein the pliable material comprises a liner having a thickness between about 100 microns and about 5 millimeters.
9. The system of claim 1 , wherein the mounting face comprises roughened surface texture.
10. The system of claim 9 , wherein the retaining face comprises a smooth surface texture.
11. The assembly of claim 9 , wherein the mounting face is at least partially coated with hydroxyapetite.
12. The assembly of claim 1 , wherein the retaining face comprises a pliable material.
13. The system of claim 12 , wherein the pliable material comprises ultra high molecular weight polyethylene.
14. The system of claim 1 , wherein the rigid, non-resorbable biocompatible material comprises a ceramic.
15. The system of claim 1 , wherein the rigid, non-resorbable biocompatible material comprises a polymer.
16. The system of claim 1 , wherein the first blocking plate has a wedge shape.
17. The system of claim 1 , wherein the rigid non-resorbable biocompatible material comprises a metal.