Conversion of joint implants

Abstract

An implant apparatus (1, 100, 200) has a distal component (10, 101, 201) with a stem for intramedullary insertion in a distal bone such as the metacarpal. A proximal component is for sliding engagement on the trapezium as is known in the art. The apparatus also has a replacement proximal component (30, 110, 210) which can be releasably connected to the distal component by threads (23, 15, 104, 115, 204, 215) so that it may replace the original proximal component during revision surgery to provide a different manner of hemi arthroplasty articulation on a proximal bone. For example, after a trapeziectomy, the replacement may extend as far proximally as the scaphoid bone for translational movement on this bone, whereas the original proximal component engaged a surface of the trapezium with translational movement. The replacement proximal component may be long enough to span the longitudinal dimension of the trapezium that has been removed, possibly by use of a bridging part (20) which is long enough to span most of this distance.

Dependencies are inferred from the claim text.