title: Factors that influence outcome in bracing large curves in patients with adolescent idiopathic scoliosis.
abstract: METHODS
  A retrospective review of 51 patients with adolescent idiopathic scoliosis (AIS) treated with a Boston brace for curves ranging from 36 degrees to 45 degrees.
  
  
  OBJECTIVE
  To determine what radiographic or clinical observations may be predictive of outcome.
  
  
  BACKGROUND
  Patients with AIS who are braced for curves >35 degrees are less likely to respond to conservative treatment than patients of similar maturity with smaller curves.
  
  
  METHODS
  Skeletally immature patients with AIS with no history of prior treatment were treated with a Boston brace. Cobb angles, vertebral tilt angles, coronal decompensation, apical vertebral translation(s), apical vertebral rotation, lateral trunk shift, rib vertebral angle difference, pelvic tilt, and the lumbar pelvic relationship (LPR) were measured at brace prescription, initial in-brace, brace discontinuation, and follow-up.
  
  
  RESULTS
  At the time of brace discontinuation, 31 patients (61%) were judged treatment successes. With follow-up observation, an additional eight patients progressed beyond 5 degrees, and a total of 16 patients (31%) required surgical correction. Only patients with double curves were found to have radiographic values predictive of outcome. The LPR angle, the association between the thoracic curve vertebral tilt angles and the amount of in-brace correction of the Cobb angle, were significant predictors. A patient's reported wear schedule significantly influenced outcome.
  
  
  CONCLUSIONS
  Patients with a double curve pattern in which the thoracic curve is >35 degrees and the LPR angle is >12 degrees are significantly more likely to demonstrate curve progression. In-brace correction for double curves of at least 25% and a patient's ability to wear the orthosis >18 hours/day significantly increased the likelihood of success.
authors.affiliation: Orthotics Department, Texas Scottish Rite Hospital for Children, Dallas, Texas 75219, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Katz
authors.forename: A A
authors.initials: AA
authors.lastname: Durrani
mesh_terms: D000293:Adolescent; D001915:Braces; D002648:Child; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D008141:Lordosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D010349:Patient Compliance; D011859:Radiography; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D013131:Spine / Q000000981:diagnostic imaging / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome