1. Department of Orthopedic Surgery, Wakayama Medical University
2. Spine Center, Dokkyo Medical University Nikko Medical Center
3. Spine Care Center, Wakayama Medical University Kihoku Hospital
4. Department of Orthopaedic Surgery, Harvard Medical School Brigham and Women's Hospital
5. Department of Orthopedic Surgery, Sumiya Orthopaedic Hospital