Is percutaneous screw fixation really superior to non-operative management after valgus-impacted femoral neck fracture: a retrospective cohort study.

PURPOSE The optimal management of valgus-impacted femoral neck fractures remains controversial. Internal fixation is associated with significant rates of re-operation, while historical non-operative management strategies consisting of prolonged bed rest also resulted in patient morbidity. Our hypothesis was that screw fixation would have comparable failure rates to non-operative treatment and immediate mobilization for valgus-impacted femoral neck fractures. METHODS Retrospective cohort at a single academic Level I trauma center of patients with valgus-impacted femoral neck fractures (AO/OTA 31-B1) treated with percutaneous screw fixation (n = 97) or non-operatively (n = 28). Operative treatment consisted of percutaneous screw fixation. Non-operative treatment consisted of early mobilization. The primary outcome was a salvage operation. Patient demographics were assessed between groups. RESULTS More non-operatively treated patients were permitted unrestricted weight-bearing (WBAT; p = 0.002). There was no increase in complication rates or mortality, and return to previous ambulatory status was comparable between operatively and non-operatively treated patients. 35.7% (10/28) of non-operatively treated patients underwent a subsequent operation, compared to 15.5% (15/97) of patients with screw fixation (p = 0.03). Only WBAT was independently associated with treatment failure (OR 3.1, 95%CI 1.2-8.3, p =0.02). WBAT was predictive of treatment failure only in the non-operatively treated group (64.3%, 9/14 WBAT vs 8.3%, 1/12 partial, p =0.005). CONCLUSION After controlling for weight-bearing restrictions, we found no difference in failure rates between non-operative treatment and screw fixation. Non-operative treatment with partial weight-bearing had low failure rates, comparable complication and mortality rates, and equivalent functional outcomes to operative treatment and is reasonable if a patient would like to avoid surgery and accepts the risk of subsequent arthroplasty. Overall, there were relatively high failure rates in all groups.