C1 Lateral Mass Screw Fixation

Abstract

C1 lateral mass screws according to Goel and Harms represent a safe and reliable stabilization of the atlas within posterior constructs. Constructs avoiding transarticular C1-C2 screws allow for different reduction manoeuvers after screw insertion. By preoperative planning, the course of the vertebral artery is visualized to avoid potentially disastrous injuries. Proper subperiosteal preparation avoids copious bleeding from the venous plexus below the C1 arch. Under lateral visualization, screws can be placed in the C1 lateral mass without the necessity of sacrificing the C2 root. C1 screws should converge about 10–20°, and bicortical screw placement is preferred.