1. Department of Orthopedic Surgery, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan 2. Institute for Integrated Sports Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan 3. Department of Clinical Biomechanics, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan