1. Department of Orthopaedic Surgery; Asan Medical Center, University of Ulsan College of Medicine; 86, Asanbyeongwongil Songpa-gu Seoul 138-736 Korea
2. Department of Orthopaedic Surgery; Borame Medical Center; 20 Boramae-ro 5-gil Dongjak-gu Seoul 156-707 Korea
3. Department of Orthopaedic Surgery; Seoul National University Hospital; 101 Daehak-ro Jongno-gu Seoul 110-744 Korea