1. Department of Orthopaedic Surgery, Shimoshizu National Hospital
2. Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University
3. Department of Orthopaedic Surgery, Eastern Chiba Medical Center
4. Department of Orthopaedic Surgery, University of Tsukuba
5. Department of Orthopaedic Surgery, St. Marianna University School of Medicine