title: Management of C1-2 traumatic fractures using an intraoperative 3D imaging-based navigation system.
abstract: OBJECTIVE
  Fractures of C-1 and C-2 are complex and surgical management may be difficult and challenging due to the anatomical relationship sbetween the vertebrae and neurovascular structures. The aim of this study was to evaluate the role, reliability, and accuracy of cervical fixation using the O-arm intraoperative 3D image-based navigation system.
  
  
  METHODS
  The authors evaluated patients who underwent a navigation system-based surgery for stabilization of a fracture of C-1 and/or C-2 from August 2011 to August 2013. All of the fixation screws were intraoperatively checked and their position was graded.
  
  
  RESULTS
  The patient population comprised 17 patients whose median age was 47.6 years. The surgical procedures were as follows: anterior dens screw fixation in 2 cases, transarticular fixation of C-1 and C-2 in 1 case, fixation using the Harms technique in 12 cases, and occipitocervical fixation in 2 cases. A total of 67 screws were placed. The control intraoperative CT scan revealed 62 screws (92.6%) correctly placed, 4 (5.9%) with a minor cortical violation (<2 mm), and only 1 screw (1.5%) that was judged to be incorrectly placed and that was immediately corrected. No vascular injury of the vertebral artery was observed either during exposition or during screw placement. No implant failure was observed.
  
  
  CONCLUSIONS
  The use of a navigation system based on an intraoperative CT allows a real-time visualization of the vertebrae, reducing the risks of screw misplacement and consequent complications.
authors.affiliation: Departments of 1 Neurosurgery and.
authors.forename: Francesco
authors.initials: F
authors.lastname: Costa
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ortolina
authors.forename: Luca
authors.initials: L
authors.lastname: Attuati
authors.forename: Andrea
authors.initials: A
authors.lastname: Cardia
authors.forename: Massimo
authors.initials: M
authors.lastname: Tomei
authors.forename: Marco
authors.initials: M
authors.lastname: Riva
authors.forename: Luca
authors.initials: L
authors.lastname: Balzarini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Fornari
mesh_terms: D000328:Adult; D000368:Aged; D001863:Bone Screws; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016103:Spinal Fractures / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods; D025321:Surgery, Computer-Assisted / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult
keywords: IGS = image-guided system; O-arm; VA = vertebral artery; cervical fracture; radiation dose; screw misplacement; spinal navigation