Objective: To determine the functional and radiological outcomes of lower third tibia closed fractures fixed by nail or plate osteosynthesis. Methodology: This randomized controlled trial included 20 patients presenting with closed fracture lower third tibia in Al-Kindy teaching hospital, Baghdad, Iraq. The patients were divided as every other one into two equal groups; group I had fractures fixed by 3.5 mm locked plate and group II by intramedullary locking nail. We followed all patients for 24 weeks to assess surgical complications, fracture union, alignment and functional outcome based on Knee society score (KSS). Results: The mean union time in both groups was 10.2 ± 1.48 and 9.3 ± 1.77 weeks, respectively (p = 0.003). Mean KSS in both groups has no significant difference (p = 0.002). Mean union time in females in the group I was higher than that of males with a significant difference (p = 0.045). In contrast, the mean KSS in males was significantly different (p = 0.017) than females. The age of the patients correlated with union time in both groups. Conclusion: Both methods are good option for fixing distal lower tibia fracture regarding the union time. No significant difference was noted in both groups in the functional outcome. Female fixed by plating may have a delay in union time and lower functional score than male
