title: Comparison of supine bending, push-prone, and traction under general anesthesia radiographs in predicting curve flexibility and postoperative correction in adolescent idiopathic scoliosis.
abstract: METHODS
  A prospective study comparing supine bending, push-prone, and traction under general anesthesia (UGA) radiographs in adolescent idiopathic scoliosis.
  
  
  OBJECTIVE
  To compare the effectiveness of 3 different flexibility methods on structural and nonstructural main thoracic (MT) and thoracolumbar/lumbar (TL/L) curves.
  
  
  BACKGROUND
  Supine side bending radiographs are the major method for determining curve reducibility. Push-prone radiographs show structural and compensatory curves on the same radiograph, but have not shown comparative reducibility in recent studies. Traction UGA is a relatively new modality which may offer similar or improved flexibility, while also showing structural and compensatory curves on the same radiograph.
  
  
  METHODS
  Fifty-eight patients with adolescent idiopathic scoliosis were prospectively studied with standing PA and lateral, supine bending and push-prone radiographs before surgery; traction UGA radiographs intraoperatively; and standing PA and lateral radiographs after surgery.
  
  
  RESULTS
  Traction UGA demonstrated equal flexibility to supine bending in structural MT and TL/L curves, with a trend towards more flexibility in severe MT curves > or = 60 degrees, while push-prone demonstrated significantly less flexibility. Each of the methods showed significantly less flexibility than postoperative correction in MT curves, while traction UGA and supine bending were not significantly different than postoperative correction in TL/L curves. Analysis of nonstructural TL/L curves showed that traction UGA and push-prone were not significantly different than postoperative correction, while supine bending overestimated postoperative correction.
  
  
  CONCLUSIONS
  Traction UGA offers flexibility equivalent to supine bending for structural MT and TL/L curves, and flexibility comparable with push-prone for nonstructural TL/L curves. Traction UGA also shows both structural and compensatory curves on the same radiograph, and ultimately may provide a better estimate of spinal balance.
authors.affiliation: Department of Orthopaedic Surgery, University Hospitals Case Medical Center, Cleveland, OH 44106, USA.
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Liu
authors.forename: Andelle L
authors.initials: AL
authors.lastname: Teng
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Armstrong
authors.forename: Connie
authors.initials: C
authors.lastname: Poe-Kochert
authors.forename: Jochen P
authors.initials: JP
authors.lastname: Son-Hing
authors.forename: George H
authors.initials: GH
authors.lastname: Thompson
mesh_terms: D000293:Adolescent; D000768:Anesthesia, General; D002648:Child; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D056888:Patient Positioning; D004856:Postural Balance; D011237:Predictive Value of Tests; D016684:Prone Position; D011446:Prospective Studies; D011859:Radiography; D016059:Range of Motion, Articular; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D012720:Severity of Illness Index; D013123:Spinal Fusion; D016683:Supine Position; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D014143:Traction; D016896:Treatment Outcome; D055815:Young Adult