Scoliosis uses the 45 to 50° threshold as a result of the well-documented, plus or minus 5° measurement error that can occur while measuring Cobb angles. Surgeons who are specialized in spine surgery perform surgery for scoliosis. To completely straighten a scoliotic spine is usually impossible, but for the most part, significant corrections are achieved. The two main types of surgery are: One or both of these surgical procedures may be needed. The surgery may be done in one or two stages and, on average, takes four to eight hours. A 50-year follow-up study published in the "Journal of the American
Management of scoliosis of bracing has not been definitively demonstrated in randomised clinical studies, with more limited studies giving inconsistent conclusions. In 2013 the Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) published results establishing benefits of bracing in adolescents with idiopathic scoliosis. In the randomized cohort, 72% in the group instructed to wear a brace for 18 hours per day against 48% in the observation group sustained curve progression to under 50 degrees, the proxy used for not requiring surgery. Additionally results suggested that the more a patient wore the brace, the better the result. In progressive infantile and sometimes juvenile scoliosis, a