Ponticulus posticus is an anomaly associated with which vertebra?

Ponticulus posticus is an anomaly associated with which vertebra?

• A. C1
• B. C2
• C. C6
• D. C7

Answer: (A)

Ponticulus posticus is a variant seen on the atlas, the first cervical vertebra, where a bony bridge forms across the groove for the vertebral artery in the posterior arch. When this bridge is complete, it creates an arcuate foramen through which the vertebral artery passes, a feature specific to the atlas. This anomaly is not a characteristic of the other cervical levels listed, so the atlas is the vertebra most closely associated with it. It’s often an incidental finding on imaging, but in some cases can relate to vertebrobasilar symptoms if the artery’s course is affected.

Ponticulus posticus is a variant seen on the atlas, the first cervical vertebra, where a bony bridge forms across the groove for the vertebral artery in the posterior arch. When this bridge is complete, it creates an arcuate foramen through which the vertebral artery passes, a feature specific to the atlas. This anomaly is not a characteristic of the other cervical levels listed, so the atlas is the vertebra most closely associated with it. It’s often an incidental finding on imaging, but in some cases can relate to vertebrobasilar symptoms if the artery’s course is affected.