Base of the skull

The base of the skull (or skull base) forms the floor of the cranial cavity and separates the brain from the structures of the neck and face.

Gross anatomy

The base of the skull is a bony diaphragm composed of a number of bones - from anterior to posterior:

These bones are separated from each other by sutures. Sutures which take part in the formation of the skull base include:


The inner surface of the base of the skull is divided by the sphenoidal ridge anteriorly and the petrous ridge posteriorly into three regions or fossae:

Additionally, a poorly-defined region termed the central base of skull is often used clinically to denote the region centred on the pituitary fossa and surrounding structures.

ADVERTISEMENT: Supporters see fewer/no ads


The base of the skull is perforated by numerous foramina which allow vessels and nerves to pass through the base of the skull allowing the intracranial cavity to communicate with the rest of the body - see main article: cranial foramina for further details.