title: Image-guided transarticular atlanto-axial screw fixation.
abstract: BACKGROUND
  The aim of this paper was to outline the use of frameless stereotaxy for the safe insertion of C1/C2 transarticular screws in the clinical setting of patients with atlanto-axial instability.
  
  
  METHODS
  A retrospective review was conducted of cases involving the use of image guidance for the accurate placement of transarticular C1/C2 screws. The outcome measures considered were neural injury, vascular injury, death, and screw placement on postoperative imaging.
  
  
  RESULTS
  We evaluated 60 patients for image-guided C1/2 transarticular screw fixation. There was a total of 109 screws inserted. There were no intraoperative complications.
  
  
  CONCLUSIONS
  Frameless stereotaxy can be applied safely in a clinical setting for transarticular screw fixation. Image guidance can facilitate preoperative planning and help determine an optimal trajectory that avoids the vertebral artery.
authors.affiliation: National Neurosurgical Unit, Dublin, Ireland.
authors.forename: M O
authors.initials: MO
authors.lastname: Kelleher
authors.forename: L
authors.initials: L
authors.lastname: McEvoy
authors.forename: J
authors.initials: J
authors.lastname: Nagaria
authors.forename: M
authors.initials: M
authors.lastname: Kamel
authors.forename: C
authors.initials: C
authors.lastname: Bolger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001268:Atlanto-Axial Joint / Q000601:surgery*; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000601:surgery; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D016268:Internal Fixators; D007593:Joint Instability / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D012189:Retrospective Studies; D012371:Robotics / Q000295:instrumentation* / Q000379:methods; D013123:Spinal Fusion / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D016896:Treatment Outcome