Ligament
Falx cerebri
Dural partition in the longitudinal cerebral fissure
High-yield
Superior sagittal sinus: attached upper border. Inferior sagittal sinus: free lower border. Straight sinus: junction of falx and tentorium.
Overview
The falx cerebri descends between the hemispheres from its attachment along the cranial midline. Its curved lower edge is free, above the corpus callosum. Posteriorly, the fold joins the tentorium. Venous sinuses follow its upper and lower margins and its junction with the tentorium.
Reference facts
- Attachments
- Anterior attachment to the frontal crest and crista galli; superior attachment along the cranial midline; posterior continuity with the tentorium near the internal occipital protuberance
- Function
- Supports separation of the hemispheres and limits relative displacement; its margins and posterior junction contain major venous sinuses
- Clinical point
- In subfalcine herniation, medial cerebral tissue is displaced beneath the falx's free inferior margin
Clinical correlation
A space-occupying lesion can push the cingulate region under the free falcine edge: subfalcine herniation. Distortion may compromise an anterior cerebral artery, reducing blood flow to medial frontal or parietal tissue and causing weakness, often prominent in the opposite leg.
Frequently asked questions
Where does the falx cerebri attach?
Anterior attachment to the frontal crest and crista galli; superior attachment along the cranial midline; posterior continuity with the tentorium near the internal occipital protuberance.
What does the falx cerebri do?
Supports separation of the hemispheres and limits relative displacement; its margins and posterior junction contain major venous sinuses.
Why does the falx cerebri matter clinically?
In subfalcine herniation, medial cerebral tissue is displaced beneath the falx's free inferior margin.