1. Department of Orthopaedics, Xuanwu Hospital Capital Medical University, Beijing 100053, China
2. National Clinical Research Center for Geriatric Diseases, Beijing 100053, China
3. Charité-Universitätsmedizin Berlin, Berlin 113353, Germany
4. Department of Interdisciplinary, Life Science, Purdue University, West Lafayette, IN 47907, USA
5. Department of Orthopaedics, Chui Yang Liu Hospital affiliated to Tsinghua University, 100020 Beijing, China