1. Department of Orthopaedics Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases Shanghai Institute of Traumatology and Orthopaedics Ruijin Hospital Shanghai Jiao Tong University School of Medicine 197 Ruijin 2nd Road Shanghai 200025 P. R. China
2. Department of Spine Surgery Renji Hospital Shanghai Jiao Tong University School of Medicine 160 Pujian Road Shanghai 200127 P. R. China
3. Department of Orthopaedics Fujian Medical University Union Hospital Xinquan Road No.29, Gulou District Fuzhou Fujian 350001 China