Preoperative traction is a risk factor for osteonecrosis of femoral head in patients with stable femoral neck fractures

To explore the relationship between preoperative traction and osteonecrosis of femoral head(ONFH)in patients with stable femoral neck fractures.Data from medical charts for 115 patients admitted to our institution with Garden II femoral neck fracture operated from January 2012 to December 2013 were extracted.Seven-year retrospective comparative study in the first affiliated hospital of Soochow University.Patients were divided into two groups by preoperative treatment:a preoperative traction group(group I)and a T-shaped shoe fixation group(group II).There were 14 patients lost to follow-up.101 patients with Garden II femoral neck fracture followed until July 2016 were available for complete analysis.Intervention:patients received skeletal traction or T-shaped shoe fixation preoperatively.All patients accepted internal fixation with multiple annulated screws.Main outcome measurements:the incidence of osteonecrosis of femoral head was analyzed based on preoperative traction,gender and implant removal.The average follow-up of these patients was 35 months(range,24-48 months).There was no implant failure or nonunion in our study.Nine patients(8.91%)had avascular necrosis.8(15.38%)patients in group I had osteonecrosis of femoral head,whereas only onepatient(2.04%)in group II had osteonecrosis of femoral head.Patients with preoperative traction had significantly higher incidence of osteonecrosis of femoral head compared with T shaped shoe fixation(P=0.032).No significant difference was found between the incidence of osteonecrosis of femoral head based on gender,age,injury-to-surgery interval time,implant removal or weight-bearing time.In patients with femoral neck fracture,preoperative traction may increase the incidence of osteonecrosis.Preoperative traction may not benefit patients with Garden II femoral neck fracture.The weight of traction may be a risk factor to osteonecrosis of femoral head.