title: Placement of iliosacral screws using 3D image-guided (O-Arm) technology and Stealth Navigation: comparison with traditional fluoroscopy.
abstract: OBJECTIVE
  We compared the accuracy, operating time and radiation exposure of the introduction of iliosacral screws using O-arm/Stealth Navigation and standard fluoroscopy.
  
  
  METHODS
  Iliosacral screws were introduced percutaneously into the first sacral body (S1) of ten human cadavers, four men and six women. The mean age was 77 years (58 to 85). Screws were introduced using a standard technique into the left side of S1 using C-Arm fluoroscopy and then into the right side using O-Arm/Stealth Navigation. The radiation was measured on the surgeon by dosimeters placed under a lead thyroid shield and apron, on a finger, a hat and on the cadavers.
  
  
  RESULTS
  There were no neuroforaminal breaches in either group. The set-up time for the O-Arm was significantly longer than for the C-Arm, while total time for placement of the screws was significantly shorter for the O-Arm than for the C-Arm (p = 0.001). The mean absorbed radiation dose during fluoroscopy was 1063 mRad (432.5 mRad to 4150 mRad). No radiation was detected on the surgeon during fluoroscopy, or when he left the room during the use of the O-Arm. The mean radiation detected on the cadavers was significantly higher in the O-Arm group (2710 mRem standard deviation (sd) 1922) than during fluoroscopy (11.9 mRem sd 14.8) (p < 0.01).
  
  
  CONCLUSIONS
  O-Arm/Stealth Navigation allows for faster percutaneous placement of iliosacral screws in a radiation-free environment for surgeons, albeit with the same accuracy and significantly more radiation exposure to cadavers, when compared with standard fluoroscopy.
  
  
  CONCLUSIONS
  Placement of iliosacral screws with O-Arm/Stealth Navigation can be performed safely and effectively. Cite this article: Bone Joint J 2016;98-B:696-702.
authors.affiliation: University of California, San Francisco, 500 Parnassus MU West 3rd Floor, San Francisco, CA, 94143, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Theologis
authors.affiliation: University of California, San Francisco, 500 Parnassus MU West 3rd Floor, San Francisco, CA, 94143, USA.
authors.forename: S
authors.initials: S
authors.lastname: Burch
authors.affiliation: University of California, San Francisco, 500 Parnassus MU West 3rd Floor, San Francisco, CA, 94143, USA.
authors.forename: M
authors.initials: M
authors.lastname: Pekmezci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D002102:Cadaver; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007085:Ilium / Q000000981:diagnostic imaging / Q000601:surgery*; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000379:methods*; D011829:Radiation Dosage; D012447:Sacrum / Q000000981:diagnostic imaging / Q000601:surgery*; D025321:Surgery, Computer-Assisted
keywords: Accuracy; Iliosacral screw; Navigation; O-Arm; Radiation exposure; Sacral fracture