title: How quantity and quality of brace wear affect the brace treatment outcomes for AIS.
abstract: OBJECTIVE
  To determine the reliability of a prognostic curve progression model and the role of the quantity and quality of brace wear for adolescent idiopathic scoliosis (AIS) brace treatment.
  
  
  METHODS
  To develop a curve progression model for full-time AIS brace treatment, 20 AIS subjects (Group 1) prescribed full-time thoracolumbar sacral orthosis (TLSO) were monitored and followed for 2 years beyond maturity. The developed curve progression model was: curve progression (in degrees) = 33 + 0.11 × Peterson risk (%) - 0.07 in-brace correction (%) - 0.45 × quality (%) - 0.48 × quantity (%) + 0.0062 × quantity × quality. To validate the model, 40 new (test) subjects (Group 2) who met the same inclusion criteria and used the same type of monitors, were monitored and followed for 2 years after bracing.
  
  
  RESULTS
  For the 40 test subjects (Group 2), the average in-brace correction was 40 ± 22 %. The average quantity and quality of the brace wear were 56 ± 19 and 55 ± 17 %, respectively. Twelve subjects (30 %) progressed of which 10 subjects (25 %) required surgery and 28 subjects (70 %) showed no progression. The accuracy of the model to determine which patients would progress was 88 % (35/40) which was better than the Peterson's risk model (68 %; 26/40) alone. Patients who had the combined quantity times the quality over a threshold 43 % had a success treatment rate of 95 %.
  
  
  CONCLUSIONS
  This study showed the prognostic model of brace treatment outcome on AIS patients treated with full-time TLSO was reliable. Both the quantity and quality of the brace wear were important factors in achieving successful brace treatment.
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, T6G2R3, Canada. elou@ualberta.ca.|Alberta Health Services-Glenrose Rehabilitation Hospital, Edmonton, AB, T5G 0H1, Canada. elou@ualberta.ca.
authors.forename: Edmond H M
authors.initials: EH
authors.lastname: Lou
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, T6G2R3, Canada.|Alberta Health Services-Glenrose Rehabilitation Hospital, Edmonton, AB, T5G 0H1, Canada.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Hill
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, T6G2R3, Canada.|Alberta Health Services-Glenrose Rehabilitation Hospital, Edmonton, AB, T5G 0H1, Canada.
authors.forename: Jim V
authors.initials: JV
authors.lastname: Raso
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, T6G2R3, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Moreau
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, AB, T6G2R3, Canada.
authors.forename: Douglas
authors.initials: D
authors.lastname: Hedden
mesh_terms: D000293:Adolescent; D001915:Braces; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory / Q000295:instrumentation; D011379:Prognosis; D012044:Regression Analysis; D015203:Reproducibility of Results; D012600:Scoliosis / Q000628:therapy*; D013997:Time Factors
keywords: Adolescent idiopathic scoliosis; Brace prediction model; Brace treatment; Quantity and quality of brace wear