1. Department of Orthopedics, Taoyuan General Hospital, Ministry of Health and Welfare, Taoyuan City 330, Taiwan
2. Department of Biochemistry, National Defense Medical Center, Taipei City 114, Taiwan
3. Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei City 114, Taiwan
4. Department of Orthopedics, Tri-Service General Hospital, National Defense Medical Center, Taipei City 114, Taiwan
5. Institute of Preventive Medicine, National Defense Medical Center, New Taipei City 237, Taiwan