Department of Orthopaedics, Chongqing General Hospital, Chongqing, 400021, People's Republic of China. Department of Orthopedics, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, People's Republic of China. liuinsistence@163.com. Department of Radiology, Chongqing Traditional Chinese Medicine Hospital, Chongqing, 400022, People's Republic of China. liuxi7979@sina.com.