1. Faculty of Medical Sciences, The University of Fukui, Department of Orthopaedics and Rehabilitation Medicine, Fukui, Japan.
2. Department of Orthopaedic Surgery, Iwamoto Orthopaedic Clinic, Osaka, Japan.
3. Research and Education Program for Life Science, The University of Fukui, Department of Orthopaedics and Rehabilitation Medicine, Fukui, Japan.