title: Accuracy of computer assisted percutaneous placement of iliosacral screws: a cadaveric study.
abstract: OBJECTIVE
  To determine the accuracy of computer-assisted fluoronavigation for percutaneous iliosacral screw placement.
  
  
  METHODS
  A fluoronavigation system (Stryker Navigation System, Stryker Leibinger, Kalamazoo, MI) was used to guide the placement of four iliosacral screws into the S-1 bodies of each of five cadaveric pelvic specimens with intact soft tissues. Accuracy of screw placement was verified by radiographs, CT scans, and direct dissection.
  
  
  RESULTS
  All 20 screws were placed accurately without complications. Nineteen screws were completely contained within the osseous "safe zone." On direct dissection, one screw was noted to have penetrated the S-1 foramina by 3 mm without impingement on the nerve root. This was not detected on radiograph or CT scan.
  
  
  CONCLUSIONS
  The results of this study support the safety and accuracy of computer-assisted fluoronavigation for iliosacral screw placement. The advantages include decreased fluoroscopic time, real-time simultaneous visualization of all three views (inlet, outlet, and lateral), and increased accuracy of placement. Clinical study is warranted.
authors.affiliation: Orthopaedic Bioengineering Laboratory, Department of Orthopaedic Surgery, University of Louisville, Louisville, Kentucky 40202, USA. Sbante01@gwise.louisville.edu
authors.forename: S B
authors.initials: SB
authors.lastname: Antekeier
authors.forename: D P
authors.initials: DP
authors.lastname: Antekeier
authors.forename: C H
authors.initials: CH
authors.lastname: Crawford
authors.forename: A L
authors.initials: AL
authors.lastname: Malkani
mesh_terms: D001863:Bone Screws; D005471:Fluoroscopy; D006801:Humans; D019637:Orthopedic Procedures; D015203:Reproducibility of Results; D012446:Sacroiliac Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed