Arcuate Foramen: Anatomy, Embryology, Nomenclature, Pathology, and Surgical Considerations

BACKGROUND: The arcuate foramen is an anatomic variant that is thought to arise from ossification of the posterior atlanto-occipital membrane. Owing to potential entrapment of the vertebral artery segment that traverses the foramen, vertebrobasilar ischemia may occur, and the person may experience vertigo, headache, or neck pain. METHODS: We reviewed the literature regarding anatomy (both human and comparative), embryology, nomenclature, pathology, and surgery of the arcuate foramen. RESULTS: Surgically, the presence of an arcuate foramen is important when placing screws into lateral masses of the atlas. In these cases, the screws can damage the V3 segment of the vertebral artery and/or the suboccipital nerve. CONCLUSIONS: It is important to review the current literature on the arcuate foramen to further understand its morphology and clinical relevance.