1. Departments of Orthopaedics, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China
2. Department of General Surgery, Xiangyang Central Hospital, The Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei 441021, P.R. China
3. Department of Nursing, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, P.R. China