1. Department of Orthopaedic Surgery, Seoul National University College of Medicine, Seoul, Korea.
2. Department of Orthopaedic Surgery, SMG-SNU Boramae Medical Center, Seoul, Korea.
3. Department of Orthopedic Surgery, Asan Medical Center, Seoul, Korea.
4. Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
5. Medical Research Center, Seoul National University, Seoul, Korea.