Opisthion

The opisthion is the median (midline) point of the posterior margin of the foramen magnum.

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

Related pathology

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

Head and neck anatomy
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Article information

rID: 40453
Section: Anatomy
Synonyms or Alternate Spellings:

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Cases and figures

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