Falx cerebelli

Anatomy

The falx cerebelli is a small midline fold of dura mater projecting anterior-ward from the skull and into the space between the cerebellar hemispheres. It generally measures between 2.8 and 4.5 cm in length, and approximately 1–2 mm in thickness.

Attachments

Superiorly, it (with its upwardly directed base) attaches at the midline to the posterior portion of the inferior surface of the tentorium cerebelli.

Posteriorly, it attaches to the internal occipital crest; the inferior-most extremity of its posterior attachment frequently divides into two small folds that terminate at either side of the foramen magnum.

Anatomical relations

The occipital sinus is contained within the posterior extremity of the falx cerebelli where it attaches to the internal occipital crest.

Anatomical variation

In its lower portion the falx cerebelli diminishes very rapidly in height and as it descends, it can divide into two smaller folds or diverging limbs, which are lost on the sides of the foramen magnum. Other variations such as duplication, triplication, absence, and fenestration are much less common. As dural venous sinuses are concurrent with the development of dural folds, duplication of the falx cerebelli is usually associated with duplicated occipital sinus. Knowledge of these variations is important in preventing iatrogenic injuries in this region.

References

References

1. (1909). "Atlas and textbook of human anatomy". Saunders.
2. Sihler, Andrew L. (1995). New Comparative Grammar of Greek and Latin. Oxford University Press. {{ISBN. 978-0-19-508345-3. Retrieved 12 March 2013.
3. Standring, Susan. (2021). "Gray's Anatomy: The Anatomical Basis of Clinical Practice". Elsavier.
4. Shoja MM, Tubbs RS, Khaki AA, Shokouhi G. A rare variation of the posterior cranial fossa: duplicated falx cerebelli, occipital venous sinus, and internal occipital crest. Folia Morphol (Warsz) 2006;65(2):171–173.
5. (1909). "Atlas and textbook of human anatomy". Saunders.
6. Shoja MM, Tubbs RS, Khaki AA, Shokouhi G. A rare variation of the posterior cranial fossa: duplicated falx cerebelli, occipital venous sinus, and internal occipital crest. Folia Morphol (Warsz) 2006;65(2):171–173.
7. Shoja MM, Tubbs RS, Loukas M, Shokouhi G, Oakes WJ. A complex dural-venous variation in the posterior cranial fossa: a triplicate falx cerebelli and an aberrant venous sinus. Folia Morphol (Warsz) 2007;66(2):148–51.
8. Tubbs Rs, Dockery SE, Salter G, Elton S, Blount JP, Grabb PA, Oakes WJ. Absence of the falx cerebelli in a Chiari II malformation. Clin Anat. 2002;15(3):193–195.
9. Shoja MM, Tubbs RS, Shokouhi GH, Ashrafian A, Oakes WJ. Abstract presented at the 23rd Annual Meeting of the American Association of Clinical Anatomists. Milwaukee, Wisconsin: 2006. A triple dural-venous variation in the posterior cranial fossa: A duplicated plus accessory falx cerebelli and an aberrant venous sinus.