1. Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Shogoin, Kawahara-cho 54, Sakyo-ku, Kyoto 606-8507, Japan
2. Department of Clinical Innovative Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
3. Department of Biomedical Statistics & Bioinformatics, Kyoto University Graduate School of Medicine, Kyoto, Japan
4. Rehabilitation Unit, Kyoto University Hospital, Kyoto, Japan