Comparison of dynamic versus static external fixation for pediatric femur fractures.

External fixation of pediatric femoral shaft fractures has the advantages of minimal dissection and early weight bearing. However, it is associated with slow healing and potential for refracture. Some surgeons have proposed that axial dynamization may improve the speed and strength of callus formation. to test this hypothesis, we performed a randomized controlled trial using 53 femur fractures in 52 patients between 1995 and 1999. Patients were randomized to receive dynamic or static fixation. Average time until early callus formation was 23.2 days for dynamic fixation and 24.9 days for static fixation (P = 0.627). Average time until complete radiographic healing was 70.1 days for dynamic fixation and 63.1 days for static fixation (P = 0.370). Similarly, the differences in time to fixator removal and to full weight bearing did not reach statistical significance. The conclusion was that axial dynamization of external fixation for pediatric femur fractures has no significant effect on time to healing or frequency of complications.