Tibial lengthening with a submuscular plate in adolescents

Patients and methods: A retrospective review was performed on 20 consecutive tibiae of 16 patients who underwent tibial lengthening with the aid of external fixator and submuscular plate. Charts and radiographs were reviewed for demographics, surgical details, and complications related to the technique.

Background: Lengthening over an intramedullary nail has become a common technique for reducing the period of external fixation. However, the technique presents difficulties in patients with an open physis or a small marrow canal. Lengthening using a submuscular plate offers a new substitute in such situations, but few studies have been undertaken to determine its efficacy in teenagers.

Results: The average age of the 16 patients was 14.3 years (range 10–17), and the amount of lengthening averaged 4.1 cm (range 3.0–5.0 cm), which represented 12.7 % of preoperative bone length (range 9.1–15.8 %). Mean time in the fixator was 60.3 days, mean external fixation index was 14.8 days/cm (range 13.2–22.5 days/cm), and mean healing index was 49.1 days/cm (range 37–59.3 days/cm). Twenty-seven complications occurred giving an overall complication rate of 1.35. Twenty of the 27 were minor complications, but 7 were major. These major complications were resolved surgically or by a resolution period exceeding 3 months. There were 3 cases of transient angular deformity of distraction callus, 2 cases of transient peroneal nerve palsy, 1 case of clamp loosening, and 1 case of plate failure. Functional results were good or excellent with an average score of 95.6 according to modified Paley’s criteria.

Conclusions: Although complications were not uncommon, tibial lengthening with a submuscular plate proved to be a reliable technique for treating limb length discrepancy in adolescents with reduced external fixation duration.

Level of evidence: Level IV, case series.