1. Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
2. Department of Orthopaedic Surgery, Gumdan Top General Hospital, Incheon, Korea.
3. Department of Orthopaedic Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
4. Kay Joint Center at Cheil Orthopaedic Hospital, Seoul, Korea.