Evolution of adolescent idiopathic scoliosis: Results of a multicenter study at 20 years’ follow-up

Abstract Introduction To date there is no consensus on therapeutic indications in adolescent idiopathic scoliosis (AIS) with curvature between 30° and 60° at the end of growth. Objective The objective of this study was to assess outcome in patients with moderate AIS. Material and methods A multicenter retrospective study was conducted. Inclusion criteria were: Cobb angle, 30–60° at end of growth; and follow-up > 20 years. The data collected were angular values in adolescence and at last follow-up, and quality of life scores at follow-up. Results A total of 258 patients were enrolled: 100 operated on in adolescence, 116 never operated on, and 42 operated on in adulthood. Mean follow-up was 27.8 years. Cobb angle progression significantly differed between the 3 groups: 3.2° versus 8.8° versus 23.6°, respectively; P  35° (OR = 4.278, P  = 0.002). There were no significant differences in quality of life scores. Discussion Patients operated on in adolescence showed little radiological progression, demonstrating the efficacy of surgical treatment for curvature greater than 50°. Curvature greater than 40° was progressive and may require surgery in adulthood. Lumbar scoliosis showed greater potential progression than thoracic scoliosis in adulthood, requiring fusion as of 35° angulation. Level of evidence IV, retrospective study.