title: Comparison of angled versus AP view radiography for post-operative evaluation of lumbosacral spondylolisthesis: a cadaveric study.
abstract: BACKGROUND
  The objective of this study was to investigate if angled radiographic views of the L5-S1 junction result in quantitatively better images in patients with lumbosacral spondylolisthesis compared to conventional AP view.
  
  
  METHODS
  Grade I lumbosacral spondylolisthesis was simulated in cadaveric specimens and repaired using pedicle screws and posterolateral bone grafting. Angled view AP radiographs were taken at different angles and analyzed at both grade I spondylolisthesis and complete reduction (to normal).
  
  
  RESULTS
  The results indicated that angled view radiographs provide better visualization of intervertebral disc height, area, and posterolateral bone graft area compared with true AP views. The optimal view was at 40 degrees for grade I spondylolisthesis, and at 25 degrees -35 degrees for complete reduction.
  
  
  CONCLUSIONS
  In addition to the dynamic radiographs currently used for evaluation of patients post-spondylolisthesis repair, an additional angled view radiograph (at 40 degrees or 25-35 degrees ) is recommended to evaluate intervertebral disc height, intervertebral area, bone graft area, and pedicle screw position.
authors.affiliation: Department of Orthopaedic Surgery, University of Toledo Medical Center, 3065 Arlington Avenue, Toledo, OH, 43614, USA.
authors.forename: Nabil A
authors.initials: NA
authors.lastname: Ebraheim
authors.forename: Jiayong
authors.initials: J
authors.lastname: Liu
authors.forename: Satheesh K
authors.initials: SK
authors.lastname: Ramineni
authors.forename: Haitham
authors.initials: H
authors.lastname: Elsamaloty
authors.forename: Alan H
authors.initials: AH
authors.lastname: Lee
authors.forename: Vishwas
authors.initials: V
authors.lastname: Patil
authors.forename: Richard A
authors.initials: RA
authors.lastname: Yeasting
authors.forename: Huilin
authors.initials: H
authors.lastname: Yang
mesh_terms: D000368:Aged; D002102:Cadaver; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012447:Sacrum / Q000000981:diagnostic imaging* / Q000601:surgery; D013168:Spondylolisthesis / Q000000981:diagnostic imaging* / Q000601:surgery