1. Department of Orthopaedics, Pudong New Area Peoples' Hospital Affiliated to Shanghai University of Medicine and Health Sciences, Shanghai 201299, P.R. China
2. Department of Orthopaedics, Shanghai Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai 200233, P.R. China
3. Department of Biomedical Engineering, College of Engineering and Applied Sciences, University of Cincinnati, Cincinnati, OH 45221, USA
4. Research Center of Disabled Rehabilitation Medicine, Yangzhi Rehabilitation Hospital, Tongji University School of Medicine, Shanghai 200129, P.R. China
5. Department of Biomedical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong, SAR 999077, P.R. China