1. Department of General Surgery, Shanxian Central Hospital, Heze, Shandong 274300, P.R. China
2. Department of Neurosurgery, Shanxian Central Hospital, Heze, Shandong 274300, P.R. China
3. Department of Trauma Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China