Intramedullary Nail-Guided Correction of Lower Extremity Long Bone Deformity: Technique and Case Series

Introduction Limb deformities of the lower extremity are frequently managed with gradual correction using external fixators. Some authors have described utilizing computer-assisted hexapod external fixators for precise intraoperative Deformity Correction (DC). However, external fixator correction is both costly and time-intensive, and intramedullary nail-guided correction (IMNG) may be an acceptable alternative. The purpose of this study was to assess the efficacy of IMNG as a non-inferior cost-effective alternative approach to lower extremity long bone DC. Methods All patients who underwent femoral or tibial IMNG at a single institution from 2006 to 2022 were retrospectively reviewed. Pre- and postoperative deformity measurements, including Mechanical Axis Deviation (MAD), Lateral Distal Femoral Angle (LDFA), Medial Proximal Tibial Angle (MPTA), and Lateral Distal Tibial Angle (LDTA), were recorded using standing hip-to-ankle radiographs. Radiographic and clinical outcomes were recorded. Results Twenty-four IMNG Deformity Correction (DC) procedures performed on 18 patients were included [10 (56%) female, mean age 30 (15-62) years, mean body mass index 31 (21-67) kg/m 2 , mean follow-up 36 (9-111) months]. There were 10 (45%) isolated femoral DC, 10 (45%) isolated tibial DC, and 2 (9%) ipsilateral femoral and tibial DC in a single operation. All patients were followed until clinical and radiographic union. Mean MAD was corrected from 42.5 ± 35.0 mm preoperatively to 10.2 ± 4.8 mm from the targeted MAD. Complications occurred in 9 (50%) patients, predominantly related to symptomatic hardware and delayed healing. The rate of soft tissue complications was 5.6%. Discussion The IMNG achieved accurate correction with lower rates of soft tissue complications compared to computer-assisted hexapod fixators. Furthermore, the rate of hardware removal with IMNG was approximately half of that seen with external fixator methods. Conclusion IMNG correction is an effective and cost-conscious technique to correct complex long bone deformities of the femur and tibia.