The Japanese orthopaedic association at one hundred: a century of Japanese orthopaedics.

BACKGROUND: The Japanese Orthopaedic Association (JOA), founded in 1926, celebrates its centennial in 2026 as one of the world's largest national orthopaedic societies. METHODS: This article reviews the historical development of the JOA during its first century and highlights major scientific, clinical, educational, and public health achievements of Japanese orthopaedics. RESULTS: The JOA has played a central role in the development of Japanese orthopaedics through specialist education, clinical practice guidelines, nationwide registries, and the promotion of basic and clinical research. Japanese orthopaedic surgeons have contributed to modern orthopaedics through pioneering surgical techniques, technological innovations, and international academic exchange. These developments have expanded the role of orthopaedics beyond the treatment of musculoskeletal disorders to encompass broader public health challenges associated with population aging and the maintenance of mobility and quality of life. CONCLUSIONS: Over the past century, Japanese orthopaedics has evolved from a small academic discipline into an internationally recognized field, alongside profound demographic and epidemiological changes, particularly the emergence of a super-aged society.