Ninety-four patients with periprosthetic distal femur fractures (PPDFs) were randomized to receive locked plating (LP; n=53) or retrograde intramedullary nailing (RIMN; n=41). The primary outcome of interest was the Timed Up and Go (TUG) test at 3 months. Secondary outcomes included the Knee Society Score (KSS), rates of nonunion, malunion, reoperation, and mortality. Outcomes were assessed at 2 weeks, 6 weeks, 3 months, 6 months, 12 months, and 24 months. Overall, the results of the study revealed no significant differences between the two fixation strategies in terms of functional outcomes, including TUG and KSS scores, at any time point. However, malunion was significantly more common in the RIMN group (36.1%) compared to the LP group (9.3%) (p=0.003). Although nonunion and reoperation occurred more frequently in the LP group, these differences were not statistically significant. The findings suggest that both LP and RIMN are viable options for managing PPDFs, with considerations needed for potential differences in malunion risk.