title: Different curve pattern and other radiographical characteristics in male and female patients with adolescent idiopathic scoliosis.
abstract: METHODS
  Retrospective radiographical study.
  
  
  OBJECTIVE
  To compare the sex differences in curve patterns and radiographical characteristics in patients who have adolescent idiopathic scoliosis (AIS).
  
  
  BACKGROUND
  Sex differences in AIS have been documented in the incidence of curve progression, response to bracing, and outcomes of surgical treatment. However, limited information is available about the relation between sex and scoliosis curve patterns and radiographical presentations.
  
  
  METHODS
  A total of 359 male and 999 female patients with AIS with major curve of 20° or more were recruited. Standard posteroanterior and lateral radiographs of spine were reviewed to classify scoliosis curve patterns as typical or atypical and to measure curve severity and thoracic kyphosis. In 351 surgically treated patients, side-bending films were used to assess curve flexibility. Comparisons between male and female patients were made by subgrouping patients according to curve patterns and severity.
  
  
  RESULTS
  Atypical curves were more frequently observed in male (19.8%) than in female patients (8.9%) (P < 0.01). Sex differences were also found in the distribution of curve types. Main thoracic curve was the most common curve type in both sexes. Furthermore, significantly higher incidence of main thoracic curve in patients with severe AIS than in patients with moderate AIS was found in male (P < 0.001) but not in female patients. In patients with severe AIS who had typical curve patterns that included a major thoracic curve, male patients had larger magnitude of thoracic curve, more severe thoracic kyphosis, and more rigid thoracic and lumbar curves than female patients.
  
  
  CONCLUSIONS
  Atypical curve patterns were more predominant in male than in female patients with AIS. The thoracic curve in male patients with AIS might have higher incidence of progression than that in female patients. The higher rigidity of both thoracic and lumbar curves in male patients with AIS with severe curves might contribute to the lower curve correction rate and poor response to brace than in female cases.
authors.affiliation: Department of Spine Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China.
authors.forename: Weijun
authors.initials: W
authors.lastname: Wang
authors.forename: Zezhang
authors.initials: Z
authors.lastname: Zhu
authors.forename: Feng
authors.initials: F
authors.lastname: Zhu
authors.forename: Chao
authors.initials: C
authors.lastname: Sun
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Wang
authors.forename: Xu
authors.initials: X
authors.lastname: Sun
authors.forename: Yong
authors.initials: Y
authors.lastname: Qiu
mesh_terms: D000293:Adolescent; D016009:Chi-Square Distribution; D018450:Disease Progression; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D011856:Radiographic Image Enhancement / Q000379:methods*; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000601:surgery; D012720:Severity of Illness Index; D012737:Sex Factors; D013131:Spine / Q000000981:diagnostic imaging* / Q000601:surgery; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery