1. Orthopaedic Biomechanics Laboratory, Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD 21205,
2. and Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
3. Orthopaedic Biomechanics Laboratory, Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD 21205
4. Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
5. Institute of Biomechanics, Nobuhara Hospital, Tatsuno, Hyogo, Japan