1. Department of Orthopaedic Surgery, Tokyo Dental College Ichikawa General Hospital
2. Shiraishi Spine Clinic
3. Department of Orthopaedic Surgery, Saiseikai Utsunomiya Hospital
4. Department of Orthopaedic Surgery, Murayama Medical Center
5. Department of Orthopaedic Surgery, Saiseikai Tobu Yokohama Hospital