Current State of Diagnosis and Treatment of AVN of the Hip

Nontraumatic avascular necrosis (AVN) of the hip affects mainly young patients and leads to secondary arthritis of the hip. In our three-decade experience, the disease is underdiagnosed as many hips reach the state of secondary arthritis before the diagnosis of AVN. The treatment for AVN of the hip is still challenging for the orthopedic surgeon since the survival of total hip arthroplasties in those young patients is inferior. Core decompression, intertrochanteric osteotomy, transtrochanteric rotational osteotomy, transtrochanteric curved varus osteotomy, nonvascularized bone transplantation, and vascularized fibula transplantation are previously reported as joint-preserving treatments for AVN patients. Well-established classification systems such as the Association Research Circulation Osseous (ARCO) classification or the Japanese Investigation Committee (JIC) classification are useful not only to predict the prognosis but also to determine the optimal joint-preserving treatment for AVN patients. In this chapter, the current state of diagnosis and treatment of AVN of the hip is summarized.