Outcomes of war related femoral neck fractures

In the civilian trauma literature, femoral neck fractures in young adults are considered an orthopedic 'urgency'. To our knowledge, there have been no studies looking at the outcomes of these injuries in the combat setting. The purpose of this study is to determine the outcomes of war related femoral neck fractures; the rates avascular necrosis associated with these injuries as well as the effect time to fixation has on the development of avascular necrosis.

We performed a retrospective review of 21 patients who sustained combat related femoral neck fractures from October 2001 through October 2013. We collected demographic data, time to fixation, time to union, incidence of avascular necrosis, as well as complications and final recreational activity status.

Our study included 21 males (100%). The average length of follow up was 19.0 (2.7-62.3) months, and the average length of radiographic follow up was 21.4 months. The average age was 25.2 (21-36) years. Displaced fractures were sustained in 71.4% of patients and 95.2% had a Pauwels' type 3 fracture. 56.9% had initial reduction and fixation within 24h of injury. Percutaneous screw fixation and dynamic hip screws were definitive fixation in 57.1% and 23.8% of patients, respectively, while the remainder had a cephalomedullary device or a salvage procedure. The average time to union was 5.5 months. There was 1 case of nonunion and 1 case of delayed union. Three of the patients (16.7%) developed avascular necrosis of the femoral head, 2 of which were initially reduced within 24h of injury. There were no statistically significant differences between time to fixation, type of reduction, or presence of displacement as a predictor of the development of avascular necrosis.

We found a high rate of displaced and high Pauwels' angle fractures, consistent with the high-energy injury mechanisms. With nearly a two-year average radiographic follow-up, the incidence of avascular necrosis was 16.7%, despite only half of our patients receiving initial reduction within 24h of injury. Urgent reduction and fixation continues to be of utmost importance to decrease the risk of femoral head avascular necrosis.