Abstract: A vascular necrosis of the hip is a common disease that usually affects a young, active patient population. As the disease progresses the undermined structural integrity of the subchondral bone leads to articular collapse and subsequent osteoarthrosis. The ideal treatment is one that hinders or arrests the progression of the disease averting articular collapse and a joint replacement surgery. Several non-surgical and surgical procedures have been described to treat avascular necrosis: core decompression, osteotomies of the hip, non-vascularized and vascularized bone grafts. The purpose of this paper is to describe a surgical strategy that attempts to address the multiple factors involved in the progression of the disease: deficits in structural support, increased intraosseous pressure and the bone healing process.

Abstract: A femoral component of a hip endoprosthesis includes a lateral supporting wedge designed to be supported by the proximal lateral femur when in use. The wedge can be an integral part of the material of the femoral component or it can be placed on a standard component by cementing or preferably by a male/female socket fit. The lateral surface of the wedge forms an angle of about 10.degree.-20.degree. with the midline of the distal portion of the stem and has an anterior-posterior width of about 8.30 mm, preferably about 10-20 mm, and a medial-lateral extension of the lateral surface of the stem of at least 10 mm, preferably 10-30 mm. An apparatus for testing the endurance of femoral components includes a cable corresponding to the ilio-tibial band. Such an apparatus more accurately models hip biomechanics and thus permits a more accurate test of the stresses on femoral component designs.

Abstract: A femoral component of a hip endoprosthesis includes a lateral supporting wedge designed to be supported by the proximal lateral femur when in use. The wedge can be an integral part of the material of the femoral component or it can be placed on a standard component by cementing or preferably by a male/female socket fit. The lateral surface of the wedge forms an angle of about 10.degree.-20.degree. with the midline of the distal portion of the stem and has an anterior-posterior width of about 8-30 mm, preferably about 10-20 mm, and a medial-lateral extension of the lateral surface of the stem of at least 10 mm, preferably 10-30 mm.