1 Department of Orthopaedic Surgery, National Hospital Organization Kure Medical Center Chu-goku Cancer Center, 3-1 Aoyama-cho, Kure, Hiroshima, 737-0023, Japan. Electronic address: hiroki8@xg7.so-net.ne.jp.
2 Department of Health Science, School of Medicine, Hiroshima University, Hiroshima, Japan.
3 Department of Orthopaedic Surgery, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
4 O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia.