title: Safety and efficacy of C2 pedicle screws placed with anatomic and lateral C-arm guidance.
abstract: METHODS
  This is a retrospective review of 150 C2 pedicle screw placements. Candidates had their C2 pedicle morphology assessed through three-dimensional imaging, including preoperative image guidance. After surgery, the patients were serially CT scanned. Follow-up, with fusion assessment, ranged from 1 to 12 years.
  
  
  OBJECTIVE
  We will show that an open technique combined with lateral C-arm guidance provides rapid placement of C2 pedicle screws.
  
  
  BACKGROUND
  C2 pedicle screws can be successful anchors for a variety of cervical problems. Standard intraoperative image guidance, biplane fluoroscopy, or free hand techniques all have their drawbacks.
  
  
  METHODS
  After adequate C2 exposure, the C2 pedicle is palpated. The dissector remains stationary to provide coronal orientation while a lateral C-arm radiograph is obtained for sagittal orientation. The drill trajectory is set, the C2 pedicle cannulated, and a cancellous screw placed.
  
  
  RESULTS
  A total of 71 patients had bilateral screws placed and 8 patients had unilateral screws placed. The overall complication rate was 2.7%.
  
  
  CONCLUSIONS
  In our series, we have found a consistent way to cannulate the C2 pedicle. C2 fixation serves as an integral part of cervical reconstruction. Preoperative planning, anatomic knowledge, and lateral C-arm orientation create a low morbidity method for C2 screw placement.
authors.affiliation: Department of Neurosurgery, Northwestern University School of Medicine, Chicago, IL, USA.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Ondra
authors.forename: Shaden
authors.initials: S
authors.lastname: Marzouk
authors.forename: Aruna
authors.initials: A
authors.lastname: Ganju
authors.forename: Thomas
authors.initials: T
authors.lastname: Morrison
authors.forename: Tyler
authors.initials: T
authors.lastname: Koski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000379:methods*; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D014057:Tomography, X-Ray Computed