Muscles - Pelvic Floor

Question 1

What resides within pelvic cavity?

Answer 1

Bladder

Rectum

Pelvic genital organs

Terminal part of the urethra

Question 2

What is the structure of the pelvic floor?

Answer 2

It is a funnel-shaped structure and separates the pelvic cavity from the perineum.

There are two (three in women) holes within the pelvic floor:

From anterior to posterior:

1) Urogenital hiatus - anteriorly positioned - allows passage of urethra (and vagina in women).

Perineal body - located between the two hiatuses, which joins the perineum to the pelvic floor.

2) Rectal hiatus - centrallly positioned - allow passage of the anal canal.

Question 3

What are the functions of the pelvic floor?

Answer 3

1) Support the abdomino pelvic organs
2) Urinary and fecal continence
3) Resist increase to intra-pelvic and abdominal pressure

Question 4

What are the components that make up the pelvic floor?

Answer 4

1) Levator ani muscles (puborectalis, pubococcygeus and the iliococcygeus)
2) Coccygeus
3) Fascia covering the muscles

Question 5

Levator ani

Answer 5

Anteriorly - pubic body

Laterally - thickened fascia of obturator internus, known as the tendinous arch

Posteriorly - ischial spine

Innervation - S2,S3 and S4

Question 6

Function of the puborectalis?

Answer 6

A U-shaped muscles that slings around the urogenital hiatus.

Main function is to maintain faecal continence. Tonic contraction bends the canal anteriorly, creating an anorectal angle (90 degress) at the anorectal junction.

Question 7

Function of iliococcygeus?

Answer 7

Elevate the pelvic floor.

Question 8

Coccygeus

Answer 8

Origin - ischial spine

Insertion - lateral aspect of the sacrum and coccyx

Innervation - S4, S5

Question 9

Clinical relevance: pelvic floor dysfunction