1. Department of Preventive Medicine, Eulji University School of Medicine, Daejeon, Korea.
2. Department of Orthopaedic Surgery, Eulji University Hospital, Daejeon, Korea.
3. Department of Orthopaedic Surgery, Gyeongsang National University Hospital, Jinju, Korea.
4. Department of Orthopaedic Surgery, Ajou University Medical Center, Suwon, Korea.
5. Department of Orthopaedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
6. Department of Orthopedic Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
7. Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.