Vertebra C2

The cervical vertebra C2 (Axis; 2nd cervical vertebra), has several key components:

1. Odontoid Process (Dens): This peg-like structure projects upward from the body of C2 and articulates with the anterior arch of C1 (atlas), allowing for the rotation of the head.

2. Body: The main anterior portion of C2, which supports the odontoid process.

3. Pedicles: These are short, thick bony projections that extend posteriorly from the body and connect to the laminae. The pedicles of C2 are important for screw fixation in spinal surgeries.[1-2]

4. Laminae: These are the bony plates that extend from the pedicles and fuse in the midline to form the posterior part of the vertebral arch.

5. Transverse Processes: These lateral projections provide attachment points for muscles and ligaments. They also contain the transverse foramina, which allow passage of the vertebral arteries.

6. Superior and Inferior Articular Facets: The superior facets articulate with the inferior facets of C1, while the inferior facets articulate with the superior facets of C3. These facets are crucial for the stability and movement of the cervical spine.

7. Pars Interarticularis (Isthmus): This is the narrow region between the superior and inferior articular processes. It is often referred to as the isthmus and is a critical area for surgical interventions.[2-3]

8. Spinous Process: The posterior projection that provides attachment for muscles and ligaments.

The C2 vertebra's unique structure, particularly the odontoid process, allows for a significant range of rotational movement, which is essential for head and neck mobility.