PROSTHESIS FOR JOINT REPLACEMENT
The invention includes a prosthesis with improved abrasive wear, comprising a composite material. The composite material may comprise an abrasive or superabrasive material dispersed in a continuous matrix of another material. The prosthesis may be formed partially or entirely of composite material, or may be coated with composite material on one or more surfaces. Embodiments include prosthetic joints and articulation surfaces comprising a composite material. Additional embodiments include methods of making a prosthesis comprising a composite material.
1 . A prosthesis, comprising:
at least two articulation surfaces;
wherein at least one of the articulation surfaces comprises an abrasive composite comprising superabrasive particles dispersed in a matrix material.
2 . The prosthesis of claim 1 , wherein the matrix material comprises metal, ceramic, or resin.
3 . The prosthesis of claim 1 , wherein the superabrasive particles are adhered to the matrix material.
4 . The prosthesis of claim 1 , wherein the superabrasive particles comprise at least about 20% of the composite.
5 . An articulation surface for use in a prosthetic joint, the articulation surface comprising:
a composite with a dispersed abrasive phase and a continuous matrix phase, said matrix being less abrasion resistant than the abrasive phase.
6 . The surface of claim 5 , wherein the matrix is comprised of a physiologically inert material.
7 . The surface of claim 5 , wherein the abrasive phase comprises superabrasive particles.
8 . An articulation surface for a prosthetic joint comprising:
a structural substrate; and
a composite coating;
wherein the composite coating comprises a dispersed abrasive particulate and a continuous matrix phase, and wherein the continuous matrix phase adheres to the abrasive particulate and to the substrate.
9 . The articulation surface of claim 8 wherein the abrasive comprises a superabrasive with hardness greater than 2000 Knoop.
10 . A prosthetic joint comprising:
a first member with an articulating bearing surface;
a second member with a second articulating surface, the second surface conforming to the first articulation surface;
wherein one or both articulating surfaces comprise a composite with dispersed particles in a continuous matrix.
11 . The joint of claim 10 wherein the particles include superabrasive particles.
12 . A prosthetic joint comprising:
an acetabular cup; and
a femoral head;
wherein the cup and head each include an articulating bearing surface;
wherein at least one of the surfaces includes a composite of dispersed abrasive particles in a continuous matrix.
13 . An implantable prosthesis, comprising:
an articulated joint with bearing surfaces;
wherein at least one of the bearing surfaces comprises a composite containing a distributed hard phase within a continuous matrix.
14 . The prosthesis of claim 11 , wherein the composite contains superabrasive particles dispersed in a matrix material.
15 . The prosthesis of claim 13 , wherein the matrix comprises metal, ceramic, or resin.
16 . The prosthesis of claim 14 , wherein the superabrasive particles are adhered to the matrix material.
17 . The prosthesis of claim 14 , wherein the superabrasive particles comprise at least about 20% of the composite.
18 . A prosthesis, comprising:
a head; and
a socket;
wherein at least one surface of the head, the socket, or both the head and socket is coated with an abrasive composite comprising superabrasive particles and a matrix material, wherein the superabrasive particles do not have significant particle-to-particle bonding.
19 . The prosthesis of claim 18 , wherein the superabrasive particle is diamond, and the composite contains no sp3 diamond-to-diamond bonding.