1. Division of Orthopedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, 1-754, Asahimachi-Dori, Chuo-Ku, Niigata City 951-8510, Niigata Prefecture, Japan
2. Department of Orthopedic Surgery, Niigata Tsubame Rosai Hospital, Sado 636, Tsubame City 959-1228, Niigata Prefecture, Japan
3. Division of Comprehensive Musculoskeletal Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City 951-8510, Niigata Prefecture, Japan
4. Division of International Health, Niigata University Graduate School of Medical and Dental Sciences, Niigata City 951-8510, Niigata Prefecture, Japan