A Retrospective Analysis of Lower Limb Deformity Correction using Three-dimensional Computed Tomography Scan

Introduction: Standard deformity correction is based on full-length true anteroposterior (AP) and lateral radiographs. However, a three-dimensional computed tomography (3D-CT) scan may provide a more intricate and detailed understanding of the deformities, to plan for the accurate correction. We present a retrospective evaluation of the deformities in three-dimensional projection with 3D-CT scans and its application on the correction of malalignment of the lower limbs. Materials and Methods: Planning of 107 cases of deformities in the lower limb was done using a 3D-CT scan over a 5-year period from September 2017. Evaluation was done by measuring angles and lines from true AP and lateral image sections of 3D-CT scans instead of standing full length lower limb radiographs (Orthoscanogram). Osteotomies were stabilized with Ilizarov fixation, followed by correction with Hexapod system (ORTHO-SUV, Pitkar, India). Results: The use of 3D-CT scan AP and lateral images provided accurate planning for deformity correction. Deformities can be understood in all three planes including rotational malalignment in a single scan. Conclusion: The precise information of the deformity in sagittal, frontal, and rotational planes is obtained by doing a 3D-CT scan, which allows for further precise planning and correction of lower limb deformities.