C2 Vertebra or Axis, Superior View

Description

Oriented in a superior (cranial) view, the second cervical vertebra (C2, axis) presents the dens (odontoid process) rising centrally from the vertebral body, with its base continuous with the centrum anteriorly and the vertebral foramen immediately posterior. Paired superior articular facets sit posterolateral to the dens and face superolaterally to receive the inferior facets of C1, while the pedicles and laminae form the posterior arch leading to the bifid spinous process. Laterally, the transverse processes bracket the vertebral foramen, and the transverse foramina lie anterolateral to the superior facets, marking the course for the vertebral artery. This viewpoint matters because C2 is the key bony element for atlantoaxial rotation, and the dens is the pivot restrained by the transverse ligament of the atlas. A small change in alignment here can be catastrophic. Odontoid fractures (Anderson and D’Alonzo types I–III) and traumatic atlantoaxial instability are interpreted by relating the dens to the facet orientation and the posterior margin of the vertebral foramen, and surgeons planning posterior C1–C2 fixation or anterior odontoid screw placement rely on these relationships. Designed for teaching spinal osteology and upper cervical biomechanics in gross anatomy, neuroanatomy, and radiology curricula, this illustration also suits trauma education materials on dens fractures and atlantoaxial instability, as well as surgical atlases covering C1 lateral mass and C2 pars/pedicle screw trajectories. Clear depiction of the superior articular surfaces and central odontoid base supports labeling, exam review, and figure adaptation for peer reviewed publications. Anatomical accuracy verified by SciePro's Medical Advisory Board.