Degeneration of the acetabular cartilage in osteonecrosis of the femoral head - Histopathologic examination of 15 hips

Acetabular cartilage with subchondral bone was taken from. the superior dom e from 15 hips of 13 patients undergoing total hip arthroplasty due to oste onecrosis of the femoral head. The mean age of the patients was 40 years. T here were 10 hips ARCO stage IIIA, and 5 hips stage IIIB. 3 of the cases we re mild, 12 moderate, and 1 had severe arthrosis. The degree of collapse of the femoral head was significantly related to the degeneration of the acet abular cartilage on histological examination. Our observations support the view that patients with an ARCO Stage III hip do not benefit from head-pres erving procedures. They may also explain why bipolar prosthesis gives poore r results than total hip arthroplasty, in cases of osteonecrosis of the fem oral head.