1. Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
2. Department of Traumatology, Qianfoshan Hospital of Shandong Province, Jinan 250000, P. R. China
3. Department of Orthopaedics, The First Hospital of Jilin University, Changchun 130021, P. R. China
4. Department of Orthopaedics and Traumatology and Li Ka Shing Institute of Health Sciences, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, SAR, P. R. China