title: [Measurement of gravity line position 15-25 years after Harrington-spondylodesis in adolescent idiopathic scoliosis].
abstract: OBJECTIVE
  A prospective analysis was performed to evaluate the relation between sagittal spinal morphology, gravity line position and morphological parameters of the pelvis and lumbar spine.
  
  
  METHODS
  25 patients with a mean follow-up of 23 (15-37) years after thoracic Harrington distraction spondylodesis were included. Standing lateral full spine radiographs were performed while patients were standing on a force plate. Pelvic angles according to Duval-Beaupere were measured.
  
  
  RESULTS
  Pelvic incidence varied from 30 degrees to 76 degrees (mean 52.1 degrees + 12.5 degrees ). Mean sacral slope was 36.4 degrees (+ 7.8 degrees ). The average thoracic kyphosis (23.6 degrees + 14.3 degrees ) and lumbar lordosis (36.4 degrees + 9.2 degrees ) were diminished. The gravity line position was on average 10.9 mm (+ 21.6mm) posterior to the center of the femoral heads.
  
  
  CONCLUSIONS
  Our method quantifies the relationship between the gravity line position and pelvic parameters according to Duval-Beaupere. The homogenous study group of patients with AIS after Harrington spondylodesis is characterized by decreased lumbar and thoracic profile and posterior displacement of the gravity line position.
authors.affiliation: Klinik und Poliklinik für Orthopädie der Eberhard-Karls-Universität Tübingen. torsten.kluba@med.uni-tuebingen.de
authors.forename: T
authors.initials: T
authors.lastname: Kluba
authors.forename: O
authors.initials: O
authors.lastname: Müller
authors.forename: S
authors.initials: S
authors.lastname: Grieb
authors.forename: G
authors.initials: G
authors.lastname: Zeger
authors.forename: J
authors.initials: J
authors.lastname: Schäfer
authors.forename: T
authors.initials: T
authors.lastname: Niemeyer
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006112:Gravitation; D006801:Humans; D016268:Internal Fixators; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D010388:Pelvis / Q000000981:diagnostic imaging / Q000503:physiopathology; D010808:Physical Examination / Q000379:methods*; D011187:Posture; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D012600:Scoliosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D016896:Treatment Outcome