Study DesignLongitudinal cohort.ObjectivesTo determine the patient-reported functional outcomes and need for related surgical procedures in a US cohort of adolescent idiopathic scoliosis (AIS) patients with minimum 20-year follow-up.Summary of Background DataThere is limited information regarding the long-term outcomes of scoliosis treatment in the US population.MethodsA novel population of patients who underwent pediatric treatment for AIS with minimum 20-year follow-up was identified. Search of a single-center diagnostic registry generated 337 patients who fulfilled the inclusion criteria (AIS, curve magnitude >35 degrees, and childhood treatment with bracing, surgery, or observation from 1975 to 1992). Any additional spine surgery as well as EQ5D, ODI, SRS 22, SAQ were determined. A total of 180 patients were included (mean of 30-year follow-up, range 20-37). Childhood treatment entailed bracing (41 patients), surgery (103 patients), and observation (36 patients).ResultsDuring the study period, only 1 of the 41 bracing patients underwent additional scoliosis-related spine surgery, whereas 5 of the 36 patients in the observation cohort underwent scoliosis surgery as adults. Seven of 103 childhood surgical patients required additional revision surgery as adults. Fifteen patients (4 braced, 7 fusion, and 4 observed) underwent chest wall surgery as adults. SRS scores were around 10% worse compared to population-based controls, with the exception of SRS mental health scores, which were similar to controls. Overall, 5.6% of patients were on disability, with no difference between operative and nonoperative groups.ConclusionWe found a low rate of adult scoliosis surgery in the braced population, and a low rate of revision surgery at the 30-year follow-up in patients undergoing spine fusion for AIS between 1975 and 1992. No detected differences in patient-reported outcomes were found between the braced, surgical, and observed populations at a mean of 30 years' follow-up.Level of EvidenceLevel III, therapeutic.