1 Department of Geriatric Surgery, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.
2 Department of Geriatrics, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.
3 Department of Orthopedics and Institute of Senile and Aging Diseases, The Second Xiangya Hospital of Central South University, Changsha, People's Republic of China.