Previous studies have compared the functional outcome and torsional differences following closed intramedullary nailing of femoral fractures. Rotational deformity following intramedullary nailing may cause symptoms and require surgical correction by osteotomy. Until now studies were designed to evaluate the correct torsional differences by examining every patient following antegrade or retrograde femoral nailing. The series included 13 women and 28 men, average age 44.5 years, who suffered a fracture of the distal femoral diaphysis. Postoperatively we established the diagnosis by three-dimensional determination of the torsion and length of the lower extremities by ultrasound measurement. Furthermore, we performed the clinical examination according to the Tegner and Lysholm score and the Merle d'Aubigne score. There were no significant differences in torsional deformity and length found. The functional outcome showed no significant differences between the two groups. The functional examination exhibited a reduction of flexion in knee motion in the retrograde group. In the antegrade group the motion of the hip was decreased. A correlation between the functional outcome and the torsional deformity was not found. The possible advantage of positioning by using the retrograde femoral nail was not verified.