Implant acetabular a center of rotation is optimized.

摘要

The implant is formed as a hemispherical metal cup (1) into which a similarly-shaped core (4) of e.g. polyethylene is fitted. The centre of curvature (O1) of the internal surface of the core coincides with the centre of rotation of the head of the femur, and is located coaxially with the centre of curvature (O2) of the cup and its crown. The core is of a thickness of 6mm or greater, and the cup extends over and arc of at least 180 deg in its median plane. A hole (8) is formed at the crown of the cup to allow more precise visual positioning of the cup relative to the bone of the cotyloidal cavity.