Anatomy study note · Back

Atlas (C1)

The first cervical vertebra. It has no body and no spinous process, only anterior and posterior arches joined by two lateral masses, and it carries the skull.

Key points

• No body, no spine: anterior + posterior arches and two lateral masses.
• Atlanto-occipital joints = nodding (“yes”).
• Atlantoaxial joints (3) = rotation (“no”).
• Transverse ligament holds the dens against the anterior arch.
• Jefferson fracture: burst ring from vertical compression.
• Occipitalization of the atlas.
• Vertebra = caudal half of one sclerotome + cranial half of the next.
• Bone: type I collagen + hydroxyapatite.
• Osteoblast builds, osteocyte maintains, osteoclast resorbs.

The full note in the atlas also covers

Features · Articulations · Action · Histology · Development · Clinical notes

Sign in free to see it on the 3D model, read the full note and practise questions on it.

Written from

• Snell’s Clinical Anatomy by Regions, 10th ed., ch. 2, PDF pp. 128–129, 143–145, 154
• Inderbir Singh’s Human Embryology, ch. 10, PDF pp. 134–137, 137
• BRS Cell Biology & Histology, 7th ed., ch. 7, PDF pp. 121–125, 130

More from the back

• Axis (C2)
• Cervical vertebrae
• Deep muscles of the back
• Intervertebral discs
• Ligaments of the vertebral column
• Lumbar vertebrae
• Spinal cord
• Spinal nerves
• Suboccipital muscles
• Thoracic vertebrae
• Thoracolumbar fascia
• Vertebral column

Privacy policy · Designed by DATXOC LLC.