1. Department of Orthopaedic Surgery, Hanyang University Hospital, Seoul, Korea.
2. Department of Orthopaedic Surgery, Hanyang University Guri Hospital, Guri, Korea.
3. Department of Orthopaedic Surgery, Kyungpook National University Hospital, Daegu, Korea.
4. Department of Orthopaedic Surgery, Yeungnam University Medical Center, Daegu, Korea.
5. Department of Orthopaedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.