Unchanged muscle function after bilateral femoral lengthening. A prospective study of 9 patients with a 2-year follow-up.

We performed pre- and 2-3.5-year postoperative isokinetic knee-testing to assess thigh muscle function in 9 patients undergoing bilateral femoral lengthening by callotasis. The median femoral lengthening was 17 (12-18) percent. The angular testing velocities were 60 degrees/sec (strength) and 180 degrees/sec (endurance). Only small changes in muscle strength were found postoperatively. Except for peak torque at 60 degrees/sec on the last-operated side (median 2 years follow-up), there were no differences between the pre- and postoperative isokinetic measurements. There were 3 major complications, 2 fractures and 1 varus deformity. 2 patients had problems with patellar pain. All patients achieved normal range of motion. They judged the final result as very good and underlined the psychological effect and the practical advantages of being taller.