Objective:To evaluate the role of high risk factors in octogenarians and nonagenarians with hip trauma,which may lead to excessive mortality and morbidity postoperatively.Methods:Fifty-four octogenarians and nonagenarians patients were enrolled in the study,receiving surgical repair of hip fracture in our hospital from January 2006 to January 2010.High risk factors were recorded preoperatively in detail.Complications and survival state were followed up by telephone for 2 years postoperatively.All the data were analyzed by Chi-square test with SPSS 13.0.Results:Twenty-six males (48.1％),aged from 80 to 94years with a mean age of 84.2 years,and twenty-eight females (51.9％),aged from 80 to 95 years with a mean age of 83.4 years,were presented in the cohort study.The hip traumas were caused by daily slight injuries (52 cases) and car accidents (2 cases),respectively.Twenty-eight patients (51.9％) with femoral neck fracture while 26 patients (48.1％)with intertrochanteric fracture were diagnosed through an anterior-posterior pelvic radiophotograph.In this series,39patients (72.2％) suffered from one or more comorbidities preoperatively.The morbidity was 48.1％ and the major cause was urinary tract infection,while a significant difference was noted between females and males.The mortality was 20.4％ with a predominant cause of acute renal failure.Conclusions:The gender should be considered as a critical high risk factor in octogenarians and nonagenarians with hip trauma postoperatively.Females are more likely to suffer complications postoperatively,which is especially obvious in senile patients over 80 years (P＜0.05).Urinary tract infection is the most frequent complication after hip surgery,followed by low limb embolism and malnutrition.The mortality is dramatically greater in patients over 80 years old than those below,and major causes are acute renal failure,multiple organ dysfunction syndrome and mental deterioration.Multidisciplinary consultations and mental assessment are encouraged in patients over 80 years old after hip trauma and surgery.Hip fractures in octogenarians and nonagenarians deserve special attention because of their advanced age and comorbidities.