Optimal Fixation Strategies for Displaced Femoral Neck Fractures in Patients 18-59 Years Old: An Analysis of 565 Cases Treated at 26 Level One Trauma Centers

To determine the difference in failure rates of surgical repair for displaced femoral neck fractures in patients less than 60 years of age according to fixation strategy. Retrospective, comparative cohort study 26 level 1 North American trauma centers Patients less than 60 years of age with a displaced femoral neck fracture (OTA 31-B2, B3) undergoing surgical repair from 2005 to 2017 Patient demographics, injury characteristics, repair methods utilized, and treatment failure (nonunion/ failed fixation, avascular necrosis, and need for secondary surgery) were compared according to fixation strategy. Five hundred and sixty-five patients met inclusion criteria and were studied. The mean age was 42 years, 36% were female, and the average Pauwels’ angle of fractures was 55°. There were 305 patients treated with multiple cannulated screws (MCS) and 260 treated with a fixed-angle (FA) construct. Treatment failures were 46% overall, but was more likely to occur in MCS constructs vs. FA devices (55% vs. 36%, p<0.001). When FA constructs were sub-stratified, the use of a sliding hip screw (SHS) with addition of a medial femoral neck buttress plate (FNBP) and “antirotation” (AR) screw demonstrated better results than either FNBP or AR screw alone or neither with the lowest overall construct failure rate of 11%(p<0.036) Historically used fixation constructs for femoral neck fractures (e.g. multiple cannulated screws and sliding hip screw) in young and middle-aged adults performed poorly compared to more recently proposed constructs, including those utilizing a medial femoral neck buttress plate and an anti-rotation screw. Fixed angle constructs outperformed multiple cannulated screws overall, and augmentation of fixed angle constructs with a medial femoral neck buttress plate and antirotation screw improved the likelihood of successful treatment. Surgeons should prioritize fixation decisions when repairing displaced femoral neck fractures in patients.