Ninety-five patients with diaphyseal tibial fractures were randomized to receive either suprapatellar (SP) intramedullary nailing (n=44) or infrapatellar (IP) intramedullary nailing (n=46). The primary outcomes were anterior knee pain measured via the visual analog scale (VAS) and patellofemoral function assessed by the Kujala score at 6 weeks and 12 months postoperatively. Secondary outcomes included fluoroscopy time, limb alignment, and complications such as malalignment and nonunion. Overall, the results revealed that the SP group experienced significantly better patellofemoral joint function at 6 weeks and 12 months and less anterior knee pain at 12 months. The findings suggest that the SP approach yields superior functional outcomes and reduced pain, supporting its potential benefits for this patient population.