Effect of dynamization in open interlocking nailing of femoral fractures. A prospective randomized comparative study of 50 cases with a 2-year follow-up.

This prospective randomized comparative study evaluated the role of dynamization of interlocking nails after open reduction and internal fixation of femoral shaft fractures. Fifty femoral shaft fractures were treated by open interlocking nailing and were statically locked. Twenty six of these 50 patients were randomly selected for dynamization and the other 24 were treated without dynamization. The patients were followed up for at least 2 years. The 26 cases which were dynamized went on to union between 13 and 28 weeks (average 19.2 weeks) with two poor results, including one nonunion. The cases that were not dynamized went on to union between 16 and 30 weeks (average 23.5 weeks) with two poor results, including one nail breakage. Though final results are comparable, the study suggests that dynamization after open interlocking nailing significantly shortens the mean time to union, though it does not significantly affect the union rate of the femoral shaft fractures.