Dr Craig Hacking et al.

The basion is the median (midline) point of the anterior margin of the foramen magnum. The apical ligament attaches to it.

It is one of the skull landmarks, craniometric points for radiological or anthropological skull measurement.

Clinical importance

Various lines and measurements using the basion are made in the diagnosis of atlanto-occipital dissociation (AOD) injuries, platybasia and basilar invagination:

Anatomy: Head and neck
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Article information

rID: 40452
Section: Anatomy
Synonyms or Alternate Spellings:

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Cases and figures

  • Skull landmarks (annotated images)
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