3.1 - Ischio-anal (ischio-rectal) Fossae

Question 1

Where do the ischio-anal fossae lie?

Answer 1

Inferior to the pelvic floor and lateral to the anal canal

Question 2

What is the purpose of the ischio-anal fossae?

Answer 2

Allow the anal canal to expand during defaecation

Question 3

What is the major content of the ischio-anal fossae and why is this area often a site of abscess formation?

Answer 3

Fat (adipose lobules)

E. coli from anal tears (?)

Question 4

A neurovascular bundle enters the ischio-anal fossae through the lesser sciatic formamen, what structures are present in this bundle and what do they supply?

Answer 4

Pudendal artery, nerve and vein
Supplies structures of the anal and genital triangles
(foramen is also called ‘Alcock’s canal’)