1. Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China.
2. Spinal division, Department of Orthopaedics, Affiliated Hospital of Guangdong Medical University, Guangdong, China.
3. Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China.
4. Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.