Intervertebral disc prosthesis

Patent metadata

Field	Value
Publication number	US-11957598-B2
Application number	US-202217727613-A
Country	US
Kind code	B2
Filing date	Apr 22, 2022
Priority date	Feb 4, 2004
Publication date	Apr 16, 2024
Grant date	Apr 16, 2024

Abstract

This disclosure relates to intervertebral disc prostheses which may have an upper plate, a lower plate, and a mobile core, with the upper surface of the core being in contact with at least a part of the lower surface of the upper plate. In some configurations, limit stops reduce friction while limiting or preventing the movements of the core relative to the lower plate, in translation and in rotation, respectively, along an axis substantially parallel to the lower plate and about an axis substantially perpendicular to the lower plate. Instrumentation for insertion of the prostheses into intervertebral spaces is also described.

First claim

The invention claimed is:

1. A motion preserving disc prosthesis comprising:
an upper plate including upper and lower surfaces;
a lower plate including upper and lower surfaces; and
a core engaging the lower surface of the upper plate and the upper surface of the lower plate, wherein at least one engaging surface of the core comprises at least one dummy hole intersecting a plurality of grooves radiating outwardly from the at least one dummy hole to facilitate engagement of the core with an adjacent portion of the upper or lower plate in response to movement by a patient, wherein the plurality of grooves are interconnected via the at least one dummy hole,
wherein the at least one dummy hole passes through only a portion of the core, wherein the at least one engaging surface of the core includes an upper surface of the core and the adjacent portion of the upper or lower plate is the lower surface of the upper plate, wherein engaging portions of the upper surface of the core and the lower surface of the upper plate are each substantially flat and wherein each of the plurality of grooves extends from the at least one dummy hole to a peripheral edge of the engaging portion of the upper surface of the core.

2. The disc prosthesis of claim 1 , wherein the at least one dummy hole passes through only a portion of the core, wherein the at least one engaging surface of the core is a lower surface of the core and the adjacent portion of the upper or lower plate is the upper surface of the lower plate, wherein engaging portions of the lower surface of the core and the upper surface of the lower plate are each substantially flat and wherein an angle formed by edges of the at least one dummy hole relative to a substantially flat engaging portion of the lower surface of the core is softened.

3. The disc prosthesis of claim 1 , wherein the at least one dummy hole and grooves are configured to receive interstitial liquid from surrounding tissue of a patient to lubricate engagement of the core relative to the adjacent portion of the upper or lower plate in response to movement by a patient.

4. The disc prosthesis of claim 1 , wherein the at least one dummy hole passes through only a portion of the core, wherein the at least one engaging surface of the core is an upper surface of the core and the adjacent portion of the upper or lower plate is the lower surface of the upper plate, wherein the at least one dummy hole is centrally located on the upper surface of the core, wherein the core comprises polyethylene, wherein each of the upper surface of the upper plate and the lower surface of the lower plate comprise a porous biocompatible coating, and wherein the upper surface of the upper plate and the lower surface of the lower plate each comprise plural teeth proximal to opposing edges of the upper plate and the lower plate, respectively, and oriented to prevent sliding of the disc prosthesis prior to adhesion of the porous biocompatible coating to osseous tissue of an adjacent vertebrae of a patient.

5. The disc prosthesis of claim 1 , wherein contacting portions adjacent to the at least one dummy hole and plurality of grooves are configured to provide a contact area between the engaging surface of the core and adjacent portion of the upper or lower plate that is substantially equal to a contact area between the lower surface of the core and the upper surface of the lower plate, whereby constraints applied to the disc prosthesis are absorbed equally by both surfaces of the core.

6. An insertion tool configured to engage the disc prosthesis of claim 1 , wherein a clip of an insertion tool comprises a U-shaped engaging surface that engages a front of the disc prosthesis, the clip further comprising a plurality of laterally opposed blades, each laterally opposed blade of the clip gripping opposing sides of the disc prosthesis, wherein at least a portion of the U-shaped engaging surface engages the upper and lower plates of the disc prosthesis, and wherein a maximum height of the clip is at least substantially equal to a total height of the front of the disc prosthesis.

7. A tool configured to engage the disc prosthesis of claim 1 , wherein a clip of a tool includes opposing blades mounted on lateral edges of the clip that grip and hold opposing sides of the disc prosthesis to maintain the disc prosthesis in a stationary position in the clip.

8. A motion preserving disc prosthesis comprising:
a first endplate including first and second surfaces;
a second endplate including first and second surfaces; and
a nucleus including first and second surfaces contacting the second surface of the first endplate and the first surface of the second endplate, respectively, wherein the first surface of the nucleus comprises at least one central recess intersecting a plurality of grooves radiating outwardly from the at least one central recess to facilitate engagement of the nucleus relative to the second surface of the first endplate in response to movement by a patient, wherein contacting portions adjacent to the at least one central recess and plurality of grooves are configured to provide a contact area between the first surface of the nucleus and second surface of the first endplate that is substantially equal to a contact area between the second surface of the nucleus and the first surface of the second endplate, whereby constraints applied to the disc prosthesis are absorbed equally by both surfaces of the nucleus, wherein the plurality of grooves are interconnected via the at least one central recess, wherein the contacting portions of the first surface of the nucleus and the second surface of the first endplate are each substantially flat and wherein an angle formed by edges of the at least one central recess relative to a substantially flat contacting portion of the first surface of the nucleus is softened.

9. The disc prosthesis of claim 8 , wherein the contacting portions of the first surface of the nucleus and second surface of the first endplate are each substantially flat and wherein each of the plurality of grooves extends from the at least one central recess to a peripheral edge of the contacting portion of the first surface of the nucleus.

10. The disc prosthesis of claim 8 , wherein the at least one central recess and grooves are configured to receive interstitial liquid from surrounding tissue of a patient to lubricate engagement of the nucleus relative to the second surface of the first endplate in response to movement by the patient.

11. The disc prosthesis of claim 8 , wherein the at least one central recess is centrally located on the first surface of the nucleus, wherein the nucleus comprises polyethylene, wherein each of the first surface of the first endplate and second surface of the second endplate comprise a porous biocompatible coating, and wherein the first surface of the first endplate and second surface of the second endplate each comprise plural teeth proximal to opposing edges of the first endplate and second endplate, respectively, and oriented to prevent sliding of the disc prosthesis prior to adhesion of the porous biocompatible coating to osseous tissue of an adjacent vertebrae of the patient.

12. The disc prosthesis of claim 8 , wherein the angle formed by edges of the at least one central recess relative to the substantially flat contact portion of the first surface of the nucleus is softened by forming a select radius at a transition of the edges of the at least one central recess.

13. A surgical kit, comprising:
a disc prosthesis comprising:
a first endplate including first and second surfaces;
a second endplate including first and second surfaces; and
a nucleus inc

Assignees

• Ldr Medical

Inventors

• Hovorka Istvan
• Bernard Pierre

Classifications

• A61F2/4425 Primary

  made of articulated components · CPC title

• A61F2/4611

  of spinal prostheses · CPC title

• A61B17/3468

  for implanting or removing devices, e.g. prostheses, implants, seeds, wires (devices for implanting seeds A61M37/0069) · CPC title

• A61B17/3472

  for bones, e.g. intraosseus injections · CPC title

• A61F2/0095

  Packages or dispensers for prostheses or other implants (for intraocular lenses A61F2/1691; for dental surgery A61C19/02) · CPC title