Lesser sciatic foramen
Foramen ischiadicum minus
- Synonym: Lesser ischiatic foramen
Definition
The posterior border of the ischium features a bony opening known as the lesser sciatic foramen. This foramen is created by the sacrotuberous and sacrospinous ligaments, which transform the "incomplete" lesser sciatic notch into a "complete" lesser sciatic foramen.
The boundaries of lesser sciatic foramen include:
Anteriorly → bony lesser sciatic notch
Posteriorly → sacrotuberous ligament
Superiorly → sacrospinous ligament
The lesser sciatic foramen serves as passageway for two significant structures:
The tendon of the obturator internus muscle as it enters the gluteal region
Internal pudendal vessels and nerves as they enter the perineum
______________________________________________________________________________
Text written by Muhammad A. Javaid, MD, PhD © 2023 IMAIOS.-+
Standring, S. and Gray, H. (2016). ‘Chapter 80: Pelvic girdle, gluteal region and thigh’ in Gray’s anatomy The anatomical Basis of Clinical Practice. (41st ed.) New York: Elsevier, pp. 1341-1345.
