1. Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
2. Department of Orthopaedic Surgery, Japan Community Health Care Organization Funabashi Central Hospital, Funabashi 273-0021, Japan
3. Department of Orthopaedic Surgery, Shimoshizu National Hospital, Yotsukaido 284-0003, Japan
4. Department of Orthopaedic Surgery, Kitasato University, Sagamihara 252-0375, Japan
5. Department of Orthopaedic Surgery, Tsuga Saito Orthopaedic Clinic, Chiba 264-0025, Japan
6. Department of Orthopaedic Surgery, Showa University, Tokyo 142-8666, Japan
7. Department of Orthopaedic Surgery, Chiba Cancer Center, Chiba 260-0801, Japan
8. Department of Orthopaedic Surgery, Sanmu Medical Center, Sanmu 289-1326, Japan
9. Department of Orthopaedic Surgery, Eastern Chiba Medical Center, Togane 283-8686, Japan
10. Department of Orthopaedic Surgery, Kumagaya General Hospital, Kumagaya 360-0013, Japan
11. Department of Orthopaedic Surgery, Japan Community Health Care Organization Chiba Hospital, Chiba 260-8710, Japan
12. Department of Orthopaedic Surgery, Chiba National Medical Center, Chiba 260-0042, Japan
13. Department of Orthopaedic Surgery, Funabashi Municipal Medical Center, Funabashi 273-8588, Japan