1. Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, P. R. China
2. School of Engineering Medicine, Beihang University, Beijing, P. R. China
3. Department of Spine Surgery, Beijing Jishuitan Hospital, Beijing, P. R. China
4. Beijing No.2 Middle School, Beijing, P. R. China
5. Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability, Key Laboratory of Technical Aids Analysis and Identification Key Laboratory of the Ministry of Civil Affairs, National Research Centre for Rehabilitation Technical Aids, Beijing, P. R. China