[Bone disease with Pain. Non-traumatic osteonecrosis of the femoral head].

Abstract The etiology and pathogenesis of non-traumatic osteonecrosis of the femoral head is still unknown although many studied has been performed. Using Magnetic resonance imaging, decision of the extent and location of the necrotic lesion, exist of bone marrow oedema has been developed. The revised criteria for diagnosis, classification, and staging of the disease from specific disease investigation committee of Japanese ministry of health, labor and welfare was established. As joint preservation operation, transtrochanteric rotational osteotomy, curved varus osteotomy were proved to be effective. Hip arthroplasty for maintaining bone stock has been developed for the treatment of young patients.