RESUMEN
The prevention of femoral head collapse and the maintenance of hip function would represent a substantial achievement in the treatment of osteonecrosis of the femoral head; however it is difficult to identify appropriate treatment protocols to manage patients with pre-collapse avascular necrosis in order to obtain a successful outcome in joint preserving procedures. Conservative treatments, including pharmacological management and biophysical modalities, are not supported by any evidence and require further investigation. The appropriate therapeutic approach has not been identified. The choice of surgical procedures is based on patient clinical conditions and anatomopathological features; preservation of the femoral head by core decompression may be attempted in younger patients without head collapse. Biological factors, such as bone morphogenetic proteins and bone marrow stem cells, would improve the outcome of core decompression. Another surgical procedure proposed for the treatment of avascular necrosis consists of large vascularized cortical bone grafts, but its use is not yet common due to surgical technical issues. Use of other surgical technique, such as osteotomies, is controversial, since arthroplasty is considered as the first option in case of severe femoral head collapse without previous intervention.