1. Department of Orthopaedic Surgery the Third Hospital of Hebei Medical University Key Laboratory of Biomechanics of Hebei Province Orthopaedic Research Institution of Hebei Province NHC Key Laboratory of Intelligent Orthopaedic Equipment No.139 Ziqiang Road Shijiazhuang 050051 P. R. China
2. 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