1. Department of Orthopaedic Surgery, Hallym University Sacred Heart Hospital, Pyeongchon-dong Dongan-gu, Anyang-si Gyeonggi-do, 431-070, Republic of Korea.
2. Department of Orthopaedic Surgery, Seoul National University College of Medicine, 28 Yeongeon-dong Jongno-gu, Seoul 110-744, Republic of Korea.