Intramedullary Nailing Following Tibia Lengthening With External Fixator in Fibular Hemimelia Reduces the Risk of Fractures

INTRODUCTION: Patients with fibular hemimelia (FH) require multistage treatment, which often includes repeated and extensive limb lengthening procedures. One of the complications of leg lengthening is tibia fracture at the level of the regenerate, which poses an even greater risk in the absence of the fibula. Possible solutions include cast immobilization or prophylactic intramedullary stabilization; however, it may be associated with a risk of infection. METHODS: All patients treated with tibial lengthening for fibular hemimelia at a single institution between 2014 and 2024 were included in the study. In total, 48 tibial lengthening procedures using circular external fixators were performed in 41 patients. After completion of lengthening and at externa fixator removal, prophylactic intramedullary nailing (Rush rods or Titanium Elastic Nails) was used in 24 cases, while a patellar tendon-bearing (PTB) cast was applied in 24 cases. Following nail implantation, antibacterial prophylaxis was administered for 10 days. The mean follow-up period from the time of external fixator removal was 56.6 months (range 18 to 109). Tibial lengthening parameters (achieved lengthening, External Fixator Index) and radiologic parameters of the regenerate (number of visible cortical walls and the Ru-Li classification) were evaluated. The prevalence of fractures, infections, unplanned reoperations, or complications during and after the lengthening process was analyzed. The data were compared between the nailing group versus non-nailng group. RESULTS: The groups were comparable in terms of sex distribution, regenerate length, regenerate quality, and External Fixator Index. The group without prophylactic intramedullary nailing was significantly older (mean 11.5 y, range 2.4 to 18.0) compared with the prophylactic nailing group (mean 7.5 y, range 2.5 to 16.6), P=0.002. No fractures occurred in patients who underwent prophylactic intramedullary nailing, whereas 6 fractures (25%) occurred in patients without prophylactic nailing (4 within the first month, 1 after 4 mo, and one 6 mo after removal of the external fixator), P=0.0229. No infections was observed in either group. CONCLUSIONS: Prophylactic intramedullary nailing performed at external fixator removal significantly reduced the risk of fractures after completion of tibial lengthening in patients with fibular hemimelia. With the use of antibiotic prophylaxis, no infections were observed following intramedullary nailing. LEVEL OF EVIDENCE: Level III.