Session 10 - The Pelvic Floor

Question 1

Where is the pelvic cavity (or true pelvis) located?

Answer 1

Lesser part of the pelvis, beneath the pelvic brim.

Question 2

Which muscle forms the posterior wall of the pelvic cavity?

Answer 2

Piriformis

Question 3

The pelvic floor separates the pelvic cavity from what?

Answer 3

The perineum

Question 4

What are the two ‘holes’ found in the pelvic floor that are particularly significant?

Answer 4

The urogenital hiatus (passage of urethra and vagina)

The rectal hiatus (passage of the anal canal)

Question 5

What is found between the urogenital hiatus and the rectal hiatus?

Answer 5

The perineal body

Question 6

What are the roles of the pelvic floor muscles?

Answer 6

Support of abdominopelvic viscera (bladder, intestines, uterus, etc.).

Resistance to increases in intra-pelvic/abdominal pressure during activities like coughing and lifting heavy objects.

Urinary and fecal continence, the muscle fibres have a sphincter action on the rectum and urethra. They relax to allow urination and defecation.

Question 7

What are the tree components of the pelvic floor?

Answer 7

Levator ani muscles
Coccyogeus muscle
Fascia coverings of the muscles

Question 8

What nerve innervates the levator ani muscles?

Answer 8

Branches of the pudendal nerve (S2-S4)

Question 9

Which three muscles make up the levator ani?

Answer 9

Puborectalis
Pubococcygeus
Iliococcygeus

Question 10

What is the main function of puborectalis?

Answer 10

To maintain faecal continence

Question 11

What is the role of the levator ani muscles during child birth?

Answer 11

Supporting the foetal head during cervix dilation during child birth

Question 12

Which muscles are most prone to damage during child birth?

Answer 12

Puborectalis and pubococcygeus (because they are situated most medially)

Question 13

What problems can damage to the levator ani muscles cause?

Answer 13

Urinary stress incontinence
Rectal incontinence

Urinary incontinence is most noticeable during activities which increase the intra-abdominal pressure, such as coughing and lifting heavy objects.

Question 14

Why might prolapse of pelvic viscera occur?

Answer 14

If there is trauma to the pelvic floor
If the pelvic floor muscles have poor tone
Prolapse of the vagina may occur if the is damage to the perineal body during child birth

Question 15

What is an episiotomy? Why are they performed?

Answer 15

A surgical cut in the perineum.

Delivered to avoid tearing of the perineum and/or the pelvic floor

Question 16

If the medial fibres of the puborectalis muscle are torn, then what kind of herniation might occur?

Answer 16

Rectal herniation

Question 17

Give some risk factors that increase the chance of prolapse of pelvic viscera.

Answer 17

Age
Number of vaginal deliveries
Family history of pelvic floor dysfunction
Weight
Chronic coughing

Question 18

How can the pelvic floor be repaired?

Answer 18

Can be repaired surgically, however a way of generally strengthening the pelvic floor muscles is to carry out pelvic floor exercises on a regular basis.

Question 19

The rectum is at an 80 degree angle to the anal canal. What muscle is responsible for marinating this angle?

Answer 19

Puborectalis. Forms puborectal sling that passes posteriorly to the anorectal junction. The tone of this muscle is responsible for maintain the angle.