Locking plate placement with unicortical screw fixation adjunctive to intramedullary rodding in long bones of patients with osteogenesis imperfecta

Abstract

Background: Intramedullary rodding has been the mainstay of long-bone stabilization in osteogenesis imperfecta. However, in some cases, intramedullary rodding cannot provide adequate fixation because of a lack of rotational control and thin diameter of long bones. We have applied adjunctive unicortical locking plate fixation in selected cases of osteogenesis imperfecta to address these biomechanical issues. Methods: Thirty-seven bone segments of twenty-four patients with osteogenesis imperfecta (ten type III, nine type IV, three type I, and two type V), in which unicortical locking plate fixation was applied adjunctive to intramedullary rodding and was later removed after union had been achieved, were the study subjects. The mean patient age at the time of surgery was 15.5 years (range, 6.2 to 39.8 years). Medical records and follow-up radiographs were reviewed to evaluate healing, complications, and the fates of screw holes after plate removal. Results: All fractures or osteotomies healed completely. Locking plates were removed postoperatively at a mean time (and standard deviation) of 1.8 +/- 0.9 years (range, 0.3 to 3.8 years). In seven of the thirty-seven cases, fractures through the screw hole occurred; all of these were treated conservatively. In eighteen of nineteen cases that were followed for more than a year after plate removal without screw hole-related complication, screw holes healed and were no longer visualized by radiography. Conclusions: Unicortical locking plate fixation effectively supplements intramedullary rod fixation in selected cases of osteogenesis imperfecta.