1. Department of Orthopaedics and Rehabilitation Medicine, Unit of Surgery, Division of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui 910‑1193, Japan
2. Department of Pediatrics, Faculty of Medical Sciences, University of Fukui, Fukui 910‑1193, Japan
3. Division of Diagnostic Pathology/Surgical Pathology, University of Fukui Hospital, Fukui 910‑1193, Japan
4. Katayama Orthopaedic Clinic, Monjyu Medical Corporation, Fukui 918‑8016, Japan