Atlas (C1; First cervical vertebral body)
The First and Second cervical vertebral bodies are unique in their shape and function. The Atlas is the First cervical vertebral body, and is also designated C1 (Cervical 1). This bone supports the skull at the Occipital-C1 articulation.
The vertebral arteries pass through the transverse foramina of the Atlas (First cervical vertebral body) which are widely spaced. The Vertebral arteries then course posteriorly and then medially over the lateral edges of C1 (Atlas, First cervical vertebral body) and pass through the dura mater into the subarachnoid space.