Femoral osteotomies for hip joint preservation.

PURPOSE: Femoral osteotomy represents one of the most distinctive achievements of Japanese orthopaedic surgery in hip preservation. Despite the remarkable advances in total hip arthroplasty (THA), preservation of the native hip joint remains an important therapeutic goal in young and active patients. This review provides a comprehensive overview of femoral osteotomies developed in Japan. METHODS: Relevant literature on Japanese femoral osteotomies was reviewed, focusing on their historical development, therapeutic principles, indications, clinical outcomes, and future perspectives. RESULTS: Japanese surgeons developed two distinctive femoral osteotomy procedures, transtrochanteric rotational osteotomy and curved varus osteotomy. These procedures have become important joint-preserving options and are currently performed primarily for osteonecrosis of the femoral head, with selected applications to other hip disorders. Long-term studies have demonstrated favorable outcomes in appropriately selected patients. However, technical complexity, demanding rehabilitation, and the widespread success of THA have limited their global adoption. CONCLUSION: Femoral osteotomy remains a valuable strategy for hip preservation and represents a unique legacy of Japanese hip surgery. Continued technological innovation and effective transmission of surgical expertise will be essential to sustain and further develop this contribution to hip-preserving surgery in the modern arthroplasty era.