Basics of Coronal Plane Deformity Correction

High tibial osteotomy (HTO) and distal femoral osteotomy (DFO) are utilized to correct knee malalignment in patients with coronal plane deformities. Identifying the deformity of the lower extremity using a standardized, reproducible approach is critical prior to correction of lower limb malalignment with an osteotomy procedure. Appropriate radiographs, including bilateral long-leg standing films, are critical to measure the anatomical and/or mechanical axes and calculate the required degree of correction. The femoral and tibial mechanical axes, malalignment (varus or valgus), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA) should be measured during coronal plane deformity analysis and accounted for during surgical planning. This paper focuses on the surgical technique for medial opening and lateral closing wedge HTO, as well as medial closing and lateral opening wedge DFO.