1. Department of Orthopaedic Surgery, Pusan National University, Yangsan Hospital, Beomeo-ri, Mulgeum-eup, Yangsan 026-770, South Korea.
2. Department of Orthopaedic Surgery, Busan Medical Centre, 1330 Geoje 2-Dong, Yeonje-Gu, Busan 611-706, South Korea.