Trapezo-metacarpal prosthesis comprises trapezoid and metacarpal components with anchoring sections and interacting convex and concave surfaces

摘要

The prosthesis consists of a trapezoid component with an anchoring section (5) and a head (6) with a large-radius convex articulation surface (7), and a metacarpal component with an anchoring section (10) for the first metacarpal bone and a concave articulation surface (15) of at least the same radius as the trapezoid component's convex surface. The base of the metacarpal component has a proximal assembly surface (12) that engages with a matching distal (13) surface on an intermediate element (11) that can be adjusted to the length of the joint being treated to give an adequate ligament tension.