Prosthesis for replacement of joints between long bones in the hand

摘要

A joint prosthesis for replacing a joint between two elongated bones of the hand. A first member is provided with an elongated stem for reception in one of the elongated bones and includes a head remote from the stem, the head having a convex articulating surface and lateral articulating surfaces adjacent the convex surface and on each side thereof. A second member has a stem for reception in the other bone and a base remote from the stem, the base having a concave articulating surface and lateral articulating surfaces on each side thereof, the concave and lateral surfaces being adapted to engage and articulate with the respective convex and lateral articulating surfaces of the first member. The lateral articulating surfaces of the first and second members being positioned to fully engage and articulate with each other to thereby restrain lateral articulation only when the bones are articulated through at least 30 degrees of flexion, and at 90 degrees of flexion, the force between said members is borne primarily by said lateral articulating surfaces.