Analysis on Influencing Factors of Avascular Necrosis of Femoral Head After Internal Fixation with Cannulated Screws in Femoral Neck Fractures

Objective To explore the multiple factors related to femoral head necrosis in patients with femoral neck fractures after cannulated screws fixation.Methods A total of 184 patients with femoral neck fracture were admitted from May,2004 to May,2006 and treated by internal fixation with cannulated screws.We retrospectively analyzed the multiple factors,including age,gender,Garden classification,the side of fracture,displacement of fracture follow-up time,procedure delay,quality of reduction,time of full-weight-loading,fixation removal,and preoperative traction.Results Complete case records were documented in 184 patients who were followed up for an average of 26.7 months.Femoral head necrosis occurred in 25 cases (13.59%).The combination of Garden stage of femoral neck fractures (OR=1.43,P=0.010),patient’s age (OR=0.19,P=0.023),quality of reduction (OR=11.49,P=0.003),and fixation removal (OR=3.184,P=0.017) was found to have the most significant influence on femoral head necrosis.Conclusions Garden stage of femoral neck fractures,patient’s age,quality of reduction and fixation removal are the major risk factors contributed to the incidence of avascular necrosis of the femoral head.