COMBINED DEROTATION CORRECTION RATE IN THE SURGICAL TREATMENT OF ADOLESCENT IDIOPATHIC SCOLIOSIS

Abstract

ABSTRACT Introduction: The surgical treatment of adolescent idiopathic scoliosis (AIS) involves several maneuvers already described to align the scoliotic curve and, subsequently, vertebral derotation. Objective: The goal is to be able to achieve the greatest possible correction, thus preserving sagittal balance parameters and leaving the greatest number of mobile segments possible. The aim of the study is to verify the combined derotation technique implemented at the Reespalda Clinic and its correction rate in idiopathic scoliosis and to evaluate implant density to achieve it. Method: Observational retrospective study collected between 2021 and 2023, with a 6-month follow-up, including clinic and radiologic data. Descriptive and inferential statistics were analyzed (R 4.3.2). Derotation technique: posterior transpedicular instrumentation with intraoperative neurophysiological monitoring, inserting a rod in a proper sagittal contour on the convex side. Specialized reduction tool with loosely affixing anchors, doing a vertebral translation. Then, a global derotation with only one rod, fixing anchors. Placing the concave rod with mild hypokyphosis. Distraction on the concave side, and compression on the convex side. Results: 25 cases were totalized (no. 15 of Lenke 1, no. 5 of Lenke 3 and no. 5 of Lenke 5). Preoperative Cobb mean angle of 60.44º and postoperative Cobb mean angle of 22.22º, with a mean correction rate of 67.45º. High screw density was related to a better correction rate (p=0.0266) in Lenke 1. Meanwhile, 100% of Lenke 3 and 5 were high density. Conclusion: Combined derotation technique reached a successful correction rate; however, high-density screw was needed to achieve it. Level of Evidence IV; Cases of Series.

Keywords

• Scoliosis
• Surgical instrumentation
• Goals