1. Department of Orthopaedic Surgery; Osaka Kosei Nenkin Hospital; 4-2-78, Fukushima, Fukushima-ku Osaka 553-0003 Japan
2. Department of Orthopaedic Surgery; Osaka University Graduate School of Medicine; Suita Japan
3. Department of Orthopaedic Surgery; Osaka General Medical Center; Osaka Japan
4. Department of Orthopaedic Biomaterial Science; Osaka University Graduate School of Medicine; Suita Japan