title: Changes in Trunk Appearance After Scoliosis Spinal Surgery and Their Relation to Changes in Spinal Measurements.
abstract: METHODS
  Retrospective study of surgical outcome.
  
  
  OBJECTIVE
  To evaluate quantitatively the changes in trunk surface deformities after scoliosis spinal surgery in Lenke 1A adolescent idiopathic scoliosis (AIS) patients and to compare it with changes in spinal measurements.
  
  
  BACKGROUND
  Most studies documenting scoliosis surgical outcome used either radiographs to evaluate changes in the spinal curve or questionnaires to assess patients health-related quality of life. Because improving trunk appearance is a major reason for patients and their parents to seek treatment, this study focuses on postoperative changes in trunk surface deformities. Recently, a novel approach to quantify trunk deformities in a reliable, automatic, and noninvasive way has been proposed.
  
  
  METHODS
  Forty-nine adolescents with Lenke 1A idiopathic scoliosis treated surgically were included. The back surface rotation and trunk lateral shift were computed on trunk surface acquisitions before and at least 6 months after surgery. We analyzed the effect of age, height, weight, curve severity, and flexibility before surgery, length of follow-up, and the surgical technique. For 25 patients with available three-dimensional (3D) spinal reconstructions, we compared changes in trunk deformities with changes in two-dimensional (2D) and 3D spinal measurements.
  
  
  RESULTS
  The mean correction rates for the back surface rotation and the trunk lateral shift are 18% and 50%, respectively. Only the surgical technique had a significant effect on the correction rate of the back surface rotation. Direct vertebral derotation and reduction by spine translation provide a better correction of the rib hump (22% and 31% respectively) than the classic rod rotation technique (8%). The reductions of the lumbar Cobb angle and the apical vertebrae transverse rotation explain, respectively, up to 17% and 16% the reduction of the back surface rotation.
  
  
  CONCLUSIONS
  Current surgical techniques perform well in realigning the trunk; however, the correction of the deformity in the transverse plane proves to be more challenging. More analysis on the positive effect of vertebral derotation on the rib hump correction is needed.
  
  
  METHODS
  III.
authors.affiliation: Polytechnique Montréal, Department of Computer and Software Engineering, P.O. Box 6079, Montréal, H3C 3A7, Québec, Canada; Sainte Justine Hospital Research Center, 3175, Chemin de la Côte-Sainte-Catherine, Montréal, H3T 1C5, Québec, Canada. Electronic address: lama.seoud@polymtl.ca.
authors.forename: Lama
authors.initials: L
authors.lastname: Seoud
authors.affiliation: Polytechnique Montréal, Department of Computer and Software Engineering, P.O. Box 6079, Montréal, H3C 3A7, Québec, Canada; Sainte Justine Hospital Research Center, 3175, Chemin de la Côte-Sainte-Catherine, Montréal, H3T 1C5, Québec, Canada.
authors.forename: Farida
authors.initials: F
authors.lastname: Cheriet
authors.affiliation: Sainte Justine Hospital Research Center, 3175, Chemin de la Côte-Sainte-Catherine, Montréal, H3T 1C5, Québec, Canada.
authors.forename: Hubert
authors.initials: H
authors.lastname: Labelle
authors.affiliation: Sainte Justine Hospital Research Center, 3175, Chemin de la Côte-Sainte-Catherine, Montréal, H3T 1C5, Québec, Canada.
authors.forename: Stefan
authors.initials: S
authors.lastname: Parent
keywords: Scoliosis; Surgical outcome; Trunk surface measurement