Effect of Sacral Slanting on Coronal Balance and Residual Curve After Lumbar Curve Correction in Adolescent Idiopathic Scoliosis: A 5-Year Follow-up Study

Study DesignRetrospective cohort study.ObjectivesSacral slanting is defined as the angle between the horizontal line and the upper endplate of the sacrum in the coronal plane. This study evaluated changes in disc wedge angle (DWA) below the lowest instrumented vertebra (LIV) and coronal balance over a 5-year follow-up in patients with adolescent idiopathic scoliosis (AIS) with structural lumbar curve exhibiting sacral slanting.MethodsThe study included 118 patients with AIS and structural lumbar curves who underwent posterior fusion to L3 or L4, with a minimum 5-year follow-up. Radiological parameters were evaluated preoperatively and at 5 years and compared between LIV-L3 and LIV-L4 groups, with subgroup analyses for high (≥5°) vs low (