AXIS (C2) ANATOMY

Axis C2 vertebra anatomy 360-degree interactive viewer showing odontoid process (dens), vertebral body, and articular surfaces

Axis (C2) - General Structure, Preview from the app. Download 3D OSTEOLOGY for full 3D control—multiple views, x-ray mode, and unlimited zoom.

GENERAL CHARACTERISTICS

What is the axis vertebra?

  • The second cervical vertebra, known as the axis, acts as the pivot for the rotation of the atlas (C1) and your skull
  • Distinguished by its robust odontoid process, also called the dens
  • The dens provides the axis of rotation allowing you to turn your head left and right

DENS AXIS (ODONTOID PROCESS)

Axis dens odontoid process 360-degree viewer showing tooth-like projection, apex, and articular surfaces

Axis - Dens (Odontoid Process), Preview from the app. Download 3D OSTEOLOGY for full 3D control—multiple views, x-ray mode, and unlimited zoom.

What is the odontoid process of the axis?

  • Strong, tooth-like projection extending upward from the body of the axis
  • Cone-shaped structure allowing the atlas and your skull to rotate around it

Apex of the Dens

What is the apex of the dens?

  • Pointed tip of the dens
  • Attachment site for the apical ligament
  • Connects to the basilar part of the occipital bone inside your skull

ARTICULAR FACETS

Axis articular facets 360-degree viewer showing anterior and posterior articular surfaces of the dens

Axis - Articular Surfaces, Preview from the app. Download 3D OSTEOLOGY for full 3D control—multiple views, x-ray mode, and unlimited zoom.

Anterior Articular Facet

What is the anterior articular facet of the dens?

  • Oval or nearly round smooth surface on the front of the dens
  • Articulates with the anterior arch of the atlas

Posterior Articular Facet

What is the posterior articular facet of the dens?

  • Shallow groove on the back of the dens, extending to the sides
  • Accommodates the transverse ligament of the atlas
  • Stabilizes the dens in place, ensuring proper articulation

BIBLIOGRAPHY

1. Henry G, Warren HL. Osteology. In: Anatomy of the Human Body. 20th ed. Philadelphia: Lea & Febiger; 1918. p. 129–97.