1. Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108 Pyung-dong, Jongno-gu, Seoul 110-746, Republic of Korea.
2. Department of Orthopaedic Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
3. Department of Radiology, Myongji Hospital, Goyang, Republic of Korea.