ISCHIOANAL FOSSA
- ischioanal fossa
- wedge shaped space on each side of anal canal below pelvic diaphragm
- boundaries
- base
- formed by skin of perineum
- apex
- formed by line wheere two fascia meet
- obturator fascia
- inferior fascia of pelvic diaphragm
- the line corresponds to origin of levator ani from pelvic wall
- anteriorly
- limited by posterior border of perineal membrane
- posteriorly fossa reaches
- lower border of gluteus maximus
- sacrotuberous ligament
- lateral wall
- is vertical
- formed by
- obturator internus
- medial surface of ischial tuberosity
- medial wall
- slopes downwards
- formed by
- levator ani with anal fascia in upper part
- external anal spinchter
- recess
- anterior recess
- extends forwards above perineal membrane
- posterior recess
- smaller than anterior
- extends deep to sacrotuberous ligament
- horseshoe recess
- connects 2 ischioanal fossa behind anal canal
- spaces and canals of fossa
- perianal space
- perianal fascia
- separates a shallow subcutaneous
- perianal space
- from deep ischioanal space
- fat arranged in loculi tightly
- so infections are painful
- ischioanal space
- large and deep
- fat arranged in loculi loosely
- by incomplete septa
- less painful infection due to less tension of swelling
- lunate fascia arches over
- ischioanal fat
- divides in to
- suprategmental space above fascia
- tegmental space below fascia
- pudendal canal
- fascial canal in lateral waal of ischioanal fossa
- encloses
- pudendal nerve
- internal pudendal vessels
- fascia is fused with lower part of obturator fascia laterally
- above
- fused with lunate fascia
- medially
- perianal fascia
- below
- falciform process of sacrotuberous ligament
- contents of ischioanal fossa
