Implant for a bone joint

Patent metadata

Field	Value
Publication number	US-10265186-B2
Application number	US-201715429635-A
Country	US
Kind code	B2
Filing date	Feb 10, 2017
Priority date	Feb 10, 2016
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

An implant (30) for a mammalian bone joint (3) for spacing a first bone (2) of the joint from a second bone (1) of the joint while allowing translational movement of the second bone in relation to the first bone is described. The implant comprises (a) a distal part (31) configured for intramedullary engagement with an end of the second bone, (b) a proximal part (34) having a platform (15) configured for non-engaging abutment of an end of the first bone and translational movement thereon, and (c) an articulating coupling (10, 16) provided between the distal and proximal ends allowing controlled articulation of the first and second bones. The bone-abutting platform is shaped to conform to and translate upon the end of the first bone. A kit for assembly to form the implant of the invention, and the use of the implant to treat osteoarthritis in a bone joint, are also described.

First claim

The invention claimed is:

1. An implant for a mammalian first carpometacarpal joint for spacing a trapezium bone of the joint from a first metacarpal bone of the joint while allowing translational movement of the first metacarpal bone in relation to the trapezium bone, the implant comprising:
(a) a distal part configured for intramedullary engagement with an end of the first metacarpal bone,
(b) a proximal part having a platform configured for non-engaging abutment of an end of the trapezium bone and translational movement thereon, the platform having a proximal surface including both a concave curvature and a convex curvature, and
(c) an articulating coupling provided between the distal and proximal parts allowing controlled articulation of the trapezium and first metacarpal bones.

2. An implant according to claim 1 in which the articulating coupling is a ball and socket joint.

3. An implant according to claim 2 in which a socket of the ball and socket joint is contained within the distal part.

4. An implant according to claim 3 in which the socket is offset towards a volar side of the distal part.

5. An implant according to claim 1 in which the distal part comprises an intramedullary stem configured for interference fit in a medullary cavity.

6. An implant according to claim 3 in which an articulating surface of the socket comprises a wear-resistant liner.

7. An implant according to claim 1 in which the concave curvature is along a longitudinal aspect of the platform and the convex curvature is along a transverse aspect of the platform.

8. An implant for a mammalian first carpometacarpal joint for spacing a trapezium bone of the joint from a first metacarpal bone of the joint while allowing translational movement of the first metacarpal bone in relation to the trapezium bone, the implant comprising:
(a) a distal part configured for intramedullary engagement with an end of the first metacarpal bone,
(b) a proximal part having a platform configured for non-engaging abutment of an end of the trapezium bone and translational movement thereon, the platform having a distal surface including a convex curvature across a longitudinal aspect of the platform, and
an articulating coupling provided between the distal and proximal portions, allowing controlled articulation of the trapezium and first metacarpal bones.

9. An implant according to claim 8 in which the articulating coupling is connected to the distal part at a location offset from a longitudinal axis of the distal part.

10. An implant according to claim 8 in which the articulating coupling is a ball and socket joint.

11. An implant according to claim 10 in which a socket of the ball and socket joint is contained within the distal part and a ball of the ball and socket joint extends distally from the convex curvature of the distal surface of the proximal part.

12. An implant according to claim 11 in which an articulating surface of the socket and/or the ball comprises a wear-resistant liner.

13. An implant according to claim 8 in which a proximal surface of the platform includes a concave curvature generally matching the convex curvature of the distal surface of the platform.

14. An implant according to claim 13 further including a convex curvature extending along a transverse aspect of the proximal surface of the platform.

15. An implant according to claim 8 in which a length of the platform along a longitudinal aspect is longer than a width of the platform along a transverse aspect.

Assignees

• Nat Univ Ireland Galway

Inventors

• Clarke Gerry
• Boland Brendan
• Bruzzi Mark
• Ladd Amy L
• Weiss Arnold-Peter C
• Stockmans Filip

Classifications

• A61F2002/30649

  Ball-and-socket joints · CPC title

• A61F2310/00161

  Carbon; Graphite · CPC title

• A61F2310/00017

  Iron- or Fe-based alloys, e.g. stainless steel · CPC title

• A61F2002/4258

  for trapezo-metacarpal joints of thumbs · CPC title

• A61F2310/00173

  Graphite · CPC title