1. Department of Orthopaedic Surgery and Rheumatology, Toho University Sakura Medical Center, Chiba, Japan
2. Department of Orthopaedic Surgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
3. Department of General Medical Sciences, Graduate School of Medicine, Chiba University, Chiba, Japan
4. Department of Orthopaedic Surgery, Eastern Chiba Medical Center, Chiba, Japan
5. Department of Pathology, Toho University Sakura Medical Center, Chiba, Japan