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.

Abstract: This invention solves the above identified limitation by providing a prosthetic implant having a porous surface layer metallurgically bonded to the implant body, wherein a barrier film of metal is positioned between a portion of the porous surface layer and the implant body at areas of stress. By preventing bonding and thereby the formation of notches at strategic locations about the implant, the overall fatigue strength of the implant may be increased. In the preferred embodiment, the film of metal is formed from molybdenum which has a higher melting temperature than titanium which is commonly used for porous layers and the implant body.By preventing notches at strategically significant areas about the implant, designers of prosthetic implants are less limited in the amount or location of the porous surface layer to be metallurgically bonded to the implant.

Abstract: This invention provides for an acetabular cup and the manufacturing of an acetabular cup implant formed from a composite of polymer materials such that the articulating surface of the implant is 100% ultra high molecular weight poly ethylene (UHMWPE) and the bone engaging surface of the cup contains a significant amount of poly methyl methacrylate (PMMA). The cup would consist of at least two zones. Zone 1 forming the articulating surface and zone two extending from the zone 1 to the bone engaging surface. Preferably, the zone 1 would consist of UHMWPE and would extend a predetermined thickness from the articulating surface. Zone 2 would preferably consist of a mixture of UHMWPE and PMMA dry blended before molding. A third zone may abut zone 2 and consist of PMMA.

Abstract: The set of implants and method of this invention provide for the conversion of an implant 10 intended for cemented fixation to a bone to an implant 10' intended for non-cemented fixation to a bone. The set of implants include a plurality of pads 20 each having a porous surface layer 24 bonded to a plate 22. A thin layer 30 of thermoplastic polymer is bonded to the opposite side of the plate 22. The implant 10 is provided with a generally smooth outer surface and is intended for cemented use for fixation to the bone. However, if during surgery, the surgeon determines that the patient may be better suited for a non-cemented implant, the modular porous pads 20 may be bonded to the implant 10 to form an implant 10' intended for non-cemented fixation to the bone.