Ipsilateral arcuate foramen and high-riding vertebral artery: implication on C1-C2 instrumentation.

Background Context: Several methods for C1-C2 stabilization have been described in the literature. These include C1-C2 transarticular and C1 lateral mass screws. In patients with aberrant anatomy such as a high-riding vertebral artery (VA) or the presence of an arcuate foramen at C1, there exists a higher risk of VA injury.