Abstract: In the subject invention, the articulating component includes a metal tray and a polyethylene bearing molded or otherwise connected to the metal tray. The distal surface of the metal tray, the surface in contact with the tibial component, is highly polished and is substantially flat. The proximal surface of the tibial component, the surface in contact with the articulating component, is likewise highly polished and substantially flat. In use, the two highly polished flat surfaces provide an environment wherein the articulating surface may freely move relative to the tibial component as the patient's knee joint is flexed and extended during movement.

Abstract: The present invention is directed to an acetabular cup prosthesis for implantation into a pelvic bone. A cup having a cavity for receiving a femoral head is formed of a polymeric material having a predetermined tensile strength. A backing is disposed about and attached to the polymeric cup. The backing has a porous construction defining interstitial pores, with the pores being sized to receive a portion of the polymeric cup therein and adapted for allowing ingrowth of the bone therein. The portion of the polymeric cup received within the pores results in an interface strength between the polymeric cup and the backing which is substantially equal to the tensile strength of the polymeric material.