1. Department of Plastic and Reconstructive Surgery Shanghai Ninth People's Hospital School of Medicine Shanghai Jiao Tong University 639 Zhizaoju Rd. Shanghai 200011 P. R. China
2. Sports Medicine Institute of Fudan University Department of Sports Medicine Huashan Hospital Fudan University Shanghai 200040 P. R. China
3. Department of Physics Shanghai Normal University Guilin Road 100 Shanghai 200234 P. R. China
4. Biophysics Group Department of Physics and Astronomy University College London Gower Street London WC1E 6BT UK
5. UCL Healthcare Biomagnetic and Nanomaterials Laboratories 21 Albemarle Street London W1S 4BS UK
6. Department of Anatomy and Physiology School of Medicine Shanghai Jiao Tong University Shanghai 200025 P. R. China
7. Department of orthopedics Affiliated Suzhou Hospital of Nanjing Medical University Suzhou 215500 P. R. China