1. Department of Medical Research and Management for Musculoskeletal Pain, 22nd Century Medical and Research Center, Faculty of Medicine, The University of Tokyo, Japan
2. Clinical Research Center for Occupational Musculoskeletal Disorders, Kanto Rosai Hospital, Japan
3. Clinical Study Support, Inc., Japan
4. Institute of Medical Science, Tokyo Medical University, Japan
5. Department of Orthopaedic and Spine Surgery, Yokohama Rosai Hospital, Japan
6. Department of Orthopaedic Surgery, Nagasaki Rosai Hospital, Japan