title: Three dimensional analysis of brace biomechanical efficacy for patients with AIS.
abstract: OBJECTIVE
  Corrective three dimensional (3D) effect of different braces is debatable. We evaluated differences in in-brace radiographic correction comparing a custom thoracic-lumbo-sacral-orthosis (TLSO) (T) brace to a Chêneau type TLSO (C) brace using 3D EOS reconstruction technology. Our primary research question was the 3D effect of brace on the spine and in particularly the apical vertebra rotation (AVR).
  
  
  METHODS
  This was a retrospective comparative analysis of patients with adolescent idiopathic scoliosis who had orthogonal AP and lateral X-rays with and without brace. A 3D image of the spine was reconstructed. Coronal, sagittal and axial spine parameters were measured before bracing and then on the first post-brace X-ray. Brace efficacy in controlling coronal, sagittal and axial parameters was evaluated.
  
  
  RESULTS
  Eighteen patients treated with the C brace and ten patients treated with the T brace were included. No difference was found regarding patients' age, gender, magnitude of Cobb angle, sagittal parameters or AVR at inclusion. Following bracing, AVR was significantly reduced by the C brace compared to the T brace [average correction of 8.2° vs. 4.9° (P = 0.02)]. Coronal and sagittal correction did not differ significantly between the two groups.
  
  
  CONCLUSIONS
  By utilizing a novel 3D reconstruction technology, we were able to demonstrate that braces differ in their immediate effects on the spine. Although clinical relevance should be evaluated in a future trial we feel that the ability to measure treatment effects in 3D, and especially the transverse plane, is an important tool when evaluating different treatments.
authors.affiliation: Pediatric Orthopedic Surgery Division, Hospital for Sick Children, 555 University Av, Toronto, ON, M5G 1X8, Canada, lebelortho@gmail.com.
authors.forename: David E
authors.initials: DE
authors.lastname: Lebel
authors.forename: Zaid
authors.initials: Z
authors.lastname: Al-Aubaidi
authors.forename: Eyun-Jung
authors.initials: EJ
authors.lastname: Shin
authors.forename: Andrew
authors.initials: A
authors.lastname: Howard
authors.forename: Reinhard
authors.initials: R
authors.lastname: Zeller
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D001915:Braces; D002648:Child; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D011859:Radiography; D012189:Retrospective Studies; D012399:Rotation; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy*; D013131:Spine / Q000000981:diagnostic imaging*