 From our experience with the aforementioned short prosthesis, the investigators have joined with Biomechanical Institute, Royal National Orthopaedic Hospital, Stanmore, London and firm Biomet developed a modern design of the above. This is a short prosthesis that is anchored in the femoral neck and the upper end of the femur metaphysis. Prosthesis made of titanium with a porous surface Bonemaster . The prosthesis is anchored during surgery by pressure-fit press-fit and in a few weeks the bone grows into the prosthesis. 