1. Department of Preventive Medicine, Ajou University School of Medicine, 5 Wonchon-Dong, Youngtong-Gu, Suwon 442-749, Korea.
2. Division of Rheumatology, Department of Internal Medicine
3. Department of Orthopaedic Surgery, Hallym University Sacred Heart Hospital, 896 Pyongchon-dong, Dongan-gu, Anyang, Kyunggi-do, 431-070, Korea.