1. Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University Kasumi, Hiroshima, Japan
2. Department of Orthopaedic Surgery, Tsuchiya General Hospital, Nakashima-cho, Hiroshima, Japan
3. Department of Orthopaedic Surgery, National Hospital Organization Kure Medical Center and Chugoku Cancer, Kure, Hiroshima, Japan