Non-traumatic osteonecrosis of the femoral head - from clinical to bench.

Non-traumatic osteonecrosis of the femoral head commonly affects young adults between the third and fifth decade of life. It is the leading cause of hip joint replacements in many Asian countries including Taiwan. The ultimate goal is the preservation of the involved hip. However, this is often challenging since early diagnosis is difficult, the etiologies are miscellaneous, the pathogenesis is unclear, and successful treatment is undetermined. As a consequence, this disease remains well-known but not fully-understood. This review provides an update of the progress from clinical studies to basic bench work in terms of natural history, risk factors, genetic predilections, diagnosis, staging, and miscellaneous therapeutic modalities.