Ball-and-socket joint prosthesis with bearing insert

Claim 1

A ball-and-socket joint prosthesis which comprises: (A) a shell element having an inside surface and an outside surface; and (B) a generally spherical ball component for insertion within (C) a bearing insert element which is open-ended at its bottom, the bottom of the insert opening to a generally spherical inside surface for receiving the ball component, the insert having an outside surface which is shaped to mate with the inside surface of the shell, the dimensions of the inside surface of the insert being such that after insertion, the ball component is allowed to freely swivel, but is retained within the insert after the insert containing the ball component is locked within the shell, the shell element and the insert element having a locking mechanism consisting of a protruding portion extending a major distance around a side surface of one element for locking engagement with an opposed mating depression in the other element, the insert having a substantially horizontal slot, situated above that portion of the locking mechanism present on the insert, which slot extends around a major portion of the insert but less than the entire periphery of the insert to thereby provide a connecting portion; the insert having a single slot extending from the bottom of the insert up to the horizontal slot to thereby form at least one movable finger attached to the remainder of the insert by the connecting portion, the single slot having a sufficient width and each finger having dimensions relative to the ball component to permit removal of the insert containing the ball component from the shell when the single slot is at least partially closed through use of a means on the insert for moving at least one finger and permitting at least partial closure of the single slot.