Prosthesis bearing component

A prosthetic bearing component formed from a composite synthetic plastics material com rising an injection molded thermoplastic polymeric matrix reinforced by a pitch based carbon fiber and having a bearing surface which has been machined with a surface roughness with a value less than Ra of 2 μm wherein the combination of thermoplastic polymeric material for the matrix and the pitch bases carbon fibers is 20% to 40% by weight pitch based carbon fibers in a 60% to 80% by weight PEEK matrix.

A carbon fiber reinforced bearing component comprising:

• a part spherical body of a thermoplastic matrix having pitch based carbon fibers embedded therein, said carbon fibers being between 10 and 50 percent of the combined weight of the carbon fiber and thermoplastic, the bearing component body having an inner part spherical bearing surface with a roughness value less than an Ra of 2 μm and has an outer surface including raised engagement features, the body has a pair of spaced apart arms with the inner bearing surface in the area of the arms being relieved with respect to said part spherical bearing surface wherein said bearing surface is substantially or part spherical with a sphericity of 0.3 μm within a solid angle of 45°.

A carbon fiber reinforced bearing component comprising:

• a part spherical body of a thermoplastic matrix having pitch based carbon fibers embedded therein, said carbon fibers being between 10 and 50 percent of the combined weight of the carbon fiber and thermoplastic, the bearing component body having an inner part spherical bearing surface with a roughness value less than an Ra of 2 μm and has an outer surface including raised engagement features, the body has a pair of spaced apart arms with the inner bearing surface in the area of the arms being relieved with respect to said part spherical bearing surface and wherein the combination of polymeric material for the matrix and the pitch based carbon fibers is 20% to 40% b weight pitch based carbon fibers in a 60% to 80% by weight PEEK matrix.