Placement of C2 laminar screws using three-dimensional fluoroscopy-based image guidance.

The use of C2 laminar screws in posterior cervical fusion is a relatively new technique that provides rigid fixation of the axis with minimal risk to the vertebral artery. The techniques of C2 laminar screw placement described in the literature rely solely on anatomical landmarks to guide screw insertion. The authors report on their experience with placement of C2 laminar screws using three-dimensional (3D) fluoroscopy-based image-guidance in eight patients undergoing posterior cervical fusion. Overall, fifteen C2 laminar screws were placed. There were no complications in any of the patients. Average follow-up was 10 months (range 3-14 months). Postoperative computed tomographic (CT) scanning was available for seven patients allowing evaluation of placement of thirteen C2 laminar screws, all of which were in good position with no spinal canal violation. The intraoperative planning function of the image-guided system allowed for 4-mm diameter screws to be placed in all cases. Using modified Odom's criteria, excellent or good relief of preoperative symptoms was noted in all patients at final follow-up.