Artificial disc prosthesis

• US 20060259146A1
• Filed: 02/24/2006
• Published: 11/16/2006
• Est. Priority Date: 04/04/2003
• Status: Active Grant

• Current Assignee: Theken Spine LLC (Orthofix Medical Inc.)
• Original Assignee: Theken Disc, LLC (Integra LifeSciences Holdings Corporation)
• Inventors: Theken, Randall R., Navarro, Richard R., Ananthan, Bharadwaj
• Granted Patent: US 7,763,076 B2
• Time in Patent Office: Days
• US Class Current: 623/17.140
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2002/30372 with additional means for limiting said translation
• CPC Class Codes: A61F 2002/30383 made by laterally inserting a protrusion, e.g. a rib into a complementarily-shaped groove
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30892 parallel
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/3097 using laser
• CPC Class Codes: A61F 2002/4666 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium

Abstract

A visco-elastic motion-limiting artificial intervertebral disc prosthesis is provided that mimics the physiologic function of a normal spinal disc. The disc comprises upper and lower endplates having therewithin channels or openings for optionally receiving one or more motion-limiting members fitted on each end with an enlarged portion. One or more compression stops is provided between the upper and lower endplates. Additionally, an elastomeric cushion is disposed between the endplates and surrounds the motion-limiting members. Also, force transducers and microelectronics can be utilized to provide data to the surgeon or the patient regarding the load state of the disc.

Claims

1. A subassembly for a spinal disc prosthesis, said subassembly comprising:

an opening-containing endplate, said opening-containing endplate having an opening suitable for insertion therethrough of internal components; and

a cover suitable to join with said opening-containing endplate suitably to cover said opening and form a continuous endplate.

2. The subassembly of claim 1, wherein said internal components comprise an elongated tension member or a ball or portion thereof suitable for placement on an end of said elongated tension member.

3. The subassembly of claim 1, further comprising a polymeric member adhered to said opening-containing endplate.

4. A subassembly for a spinal disc prosthesis, said subassembly comprising:

a first endplate and a second endplate each suitable to attach to respective vertebrae; and

a polymeric member interposed between and adhered to said first and second endplates,

wherein said first endplate comprises an opening,

a subplate containing a hole, said subplate being suitable to cover said opening; and

a cover suitable to cover said hole.

5. The subassembly of claim 4, wherein said polymeric member has a polymeric member interior space having a polymeric member interior space cross-section, and said opening in said endplate is approximately dimensionally equal to said polymeric member interior space cross-section.

6. The subassembly of claim 4, wherein said first endplate and said covering components both comprise a metal.

7. The subassembly of claim 6, wherein said covering components are welded, or capable of being welded, to said endplate.

8. A subassembly for a spinal disc prosthesis, said subassembly comprising:

a first endplate and a second endplate each suitable to attach to respective vertebrae; and

a polymeric member interposed between and adhered to said first and second endplates,

wherein said first endplate comprises a bone-facing side and a non-bone-facing side, and wherein said bone-facing side of said endplate has a cavity suitable to contain electronics.

9. The subassembly of claim 8, in combination with a cover suitable to close said cavity.

10. The subassembly of claim 9, wherein said first endplate and said cover both comprise a metal.

11. The subassembly of claim 9, wherein said cover is welded, or capable of being welded, to said first endplate.

12. The subassembly of claim 8, wherein said polymeric member has a polymeric member internal opening having a polymeric member internal cross-section near said electronics-containing endplate, and wherein the bone-side said cavity having a cavity cross-section, and wherein said cavity cross-section is larger than said polymeric member internal cross-section.

13. An elongated tension member for a spinal disc prosthesis, said member comprising:

an elongated central region having two ends, and, on each of said ends, a respective ball or portion thereof having a respective convex surface, said convex surfaces facing toward each other.

14. The member of claim 13, wherein each of said balls or portions thereof is larger than a respective opening in a corresponding socket in a corresponding endplate of said spinal disc prosthesis.

15. A method of manufacturing a spinal disc prosthesis, said method comprising:

manufacturing a first endplate and a second endplate, said endplates being suitable to attach to respective vertebrae, wherein said endplates include respective sockets; and

joining a ball or portion thereof onto at least one end of an elongated member.

16. The method of claim 15, wherein said joining comprises welding.

17. The method of claim 15, further comprising, after said joining said ball or portion thereof, sealing a cover suitably to cover an immediate vicinity of said ball.

18. A method of manufacturing a spinal disc prosthesis, said method comprising:

manufacturing a first endplate and a second endplate, at least said first endplate being an opening-containing endplate containing an opening;

inserting molding cores through said opening, said molding cores being suitable to define polymeric material interior space;

molding a polymer which is interposed between and adhered to said first opening-containing endplate and said second endplate;

removing said molding cores; and

attaching a cover to said frame, said cover being suitable to close said polymeric material interior space.

19. The method of claim 18, further comprising, prior to said closing, installing components in said polymeric material interior space.