The Temporal Fossa
The temporal fossa is a depression on the temporal region and one of the largest landmarks on the skull. The temporal bone, the sphenoid bone, the parietal bone and the frontal bone contribute to its concave wall. It is superior to the infratemporal fossa which lies beneath the zygomatic arch.
Both superiorly and posteriorly the temporal fossa is bordered by the superior temporal line (origin of the deep temporal fascia). The inferior border runs along the zygomatic arch. Lastly, the anterior border is marked by the frontal process of the zygoma and the zygomatic process of the frontal bone.
The temporal fossa serves as a site of origin for the temporal muscle. It originates from the superior, anterior and posterior borders of the temporal fossa and resides within its concavity as the muscle fibers move towards their insertion point, which lies under the zygomatic arch.
The superior temporal artery, a terminal branch of the external carotid artery, courses above the superficial temporal fascia. It branches off the medial temporal artery to the temporal muscle and two smaller arteries to the scalp (frontal and parietal branches).
The artery is accompanied by the superior temporal vein. The medial vein runs between the two layers of the temporal fascia.
The fossa contains four branches from four different nerve bundles. The terminal branches include:
- a branch of the mandibular nerve (V3)
- the anterior and posterior branches of the deep temporal nerve
- the auriculotemporal nerve
- the temporal branches of the facial nerve.
The temporal fossa has the following borders:
- Superiorly and posteriorly - superior temporal line
- Inferiorly - zygomatic arch
- Anteriorly - frontal process of the zygoma and zygomatic process of the frontal bone
Its contents consist of: