Accessory ossicle of the anterior arch of the atlas

The accessory ossicle of the anterior arch of the atlas is a normal variant and is best appreciated on a lateral cervical/sagittal study. It is observed as a circular and corticated osseous density that articulates with the inferior aspect of the anterior arch of the atlas. 

It is not associated with patient symptomatology. Historical and clinical correlation of injury or other disease states may reveal the other differential considerations as possibilities, if radiographic findings are non-specific. 

Differential diagnosis


Spinal anatomy
Edit Article Share Article

Article Information

rID: 19582
Section: Anatomy
Tags: variant, cases
Synonyms or Alternate Spellings:
  • Accessory ossicle at the anterior arch of the atlas
  • Drag
    Figure 1
    Drag here to reorder.
  • Drag
    Case 1
    Drag here to reorder.
  • Drag
    Case 2
    Drag here to reorder.
  • Drag
    Case 3
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert_accept

    Error Unable to process the form. Check for errors and try again.

    Alert_accept Thank you for updating your details.