1. Department of Orthopaedic Surgery, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao 266000, P. R. China
2. Department of Orthopaedic Surgery, Qingdao Municipal Hospital, Qingdao University, No.1 Jiaozhou Road, Qingdao 266000, P. R. China
3. School of Materials and Chemistry, University of Shanghai for Science and Technology, No. 516 Jungong Road, Shanghai 200093, P. R. China
4. Trauma Emergency Center of the Third Affiliated Hospital of Hebei Medical University, No.139 Ziqiang Road, Shijiazhuang 050051, P. R. China