Single versus dual fixation of distal femur fractures: A retrospective cohort study at a level one trauma centre in New Zealand

Background The study compares single versus combination fixation of distal femur fractures. Method We retrospectively reviewed patients over 60 between January 2016 and December 2022. Union rate, ambulatory status and complication rate were primary outcomes. Secondary outcomes included quality of reduction, operative time and rate of blood transfusion. Results A total of 92 patients received single fixation, and 22 patients received combination fixation. There was no difference in rate or time of fracture union. Patients with dual fixation were allowed to weight bear on discharge significantly more than single fixation patients (50% vs. 18.9%, p = 0.003). Intramedullary nail fixation, as a single method or combined with lateral plating, was associated with earlier weight bearing. Immediate post-operative weight bearing significantly increased the likelihood of discharging to home or rehabilitation versus discharging to a transitional care facility ( p < 0.00001). There was no difference in the rate of blood transfusion, complication or mortality. Medial translation of the distal articular block was significantly lower with dual fixation (1.2% vs. 3.4%, p = 0.021). Operation time was longer with combination fixation (183 min vs. 134 min p < 0.001). Conclusion Combination fixation allows earlier weight bearing, at the cost of longer operation time.