5) The Pelvic Floor

Question 1

What is the pelvic floor formed by?

Answer 1

Pelvic diaphragm - coccygeus & levator ani
Superficial muscles & structures
- anterior (urogenital) perineum
- posterior (anal) perineum

Question 2

Where does the pelvic diaphragm lie?

Answer 2

Within the lesser pelvis

Separates pelvic cavity from perineum

Question 3

What is the function of the pelvic floor?

Answer 3

Supports pelvic viscera
Sphincter action on rectum & vagina
Can resist increases in intra-abdominal pressure
(coughing, heavy lifting, defaecation)

Question 4

What is the anterior (urogenital) perineum/diaphragm?

Answer 4

Fills the gap of the pubic arch stretching between the converging ischiopubic rami
‘Triangular sandwich’
Contains bulbourethral glands
Pierced by urethra & vagina

Question 5

What is the triangular sandwich of the urogenital perineum made up of? (2x fascia, 1x muscle)

Answer 5

Superior fascia
Sphincter urethrae - striated muscles fibres
Inferior or superficial fascia - thickened (perineal membrane)

Question 6

What lies below the perineal membrane in the male

Answer 6

Superficial transverse perineal membrane
Bulbospongiosus muscle
Ischiocavernous muscle

Question 7

What lies below the perineal membrane in both sexes

Answer 7

Superficial perineal pouch

site of urine collection if urethra ruptured below perineal membrane

Question 8

What is the posterior (anal) perineum?

Answer 8

Triangle between the ischial tuberosities & coccyx

Comprised of anus, levator ani, ischiorectal fossae

Question 9

What is the ischiorectal fossae?

Answer 9

Fatty fossa
May become infected (spreads behind anus)
Pudendal nerve passes along lateral wall of fossa

Question 10

What are the major muscle groups in the pelvic floor?

Answer 10

Levator Ani muscles
 - Puborectalis
 - Pucococcygeus
 - Iliococcygeus
Coccygeus

Question 11

What are the levator ani muscles?

Answer 11

Paired muscles, forming 3 slings of muscle

Extend from posterior aspect of pubic bone, fascia over obturator internus & ischial spines

Question 12

What are the 3 slings comprised by the levator ani muscles?

Answer 12

• Anterior fibres around prostate/vagina
• Intermediate fibres around rectum (Puborectalis) & into the anococcygeal body (Pubococcygeus)
• Posterior fibres to the anococcygeal body & coccyx (Iliococcygeus)

Question 13

What is the role of the perineal body?

Answer 13

Pyramidal fibromuscular mass
Between urogenital & anal triangles
Essential for integrity of pelvic floor
Anchors perineal muscles & rectum

Question 14

Where is the perineal body located?

Answer 14

Males between bulb of penis & anus

Females between vagina & anus

Question 15

The perineal body is a point of attachment for which muscles?

Answer 15

Anal sphincters
Bulbospongiosus
Superficial transverse perineal muscles
Fibres of levator ani

Question 16

What is an episiotomy?

Answer 16

Planned surgical incision on the perineum between the vagina and anus

Question 17

When is an episiotomy necessary?

Answer 17

To avoid rupture of perineal body during childbirth

prevents weakening of pelvic floor & prolapse of structures (vagina & uterus)

Question 18

What are the risk factors for pelvic floor dysfunction?

Answer 18

Age
Menopause (atropy of tissues)
Obesity
Chronic cough
Intrinisic connective tissue laxity

Question 19

How may the pelvic floor be damaged?

Answer 19

Childbirth
Prolapse of organs
Stress incontinence

Question 20

If the pelvic floor is damaged, what consequences will this have on nearby nerves, muscles & ligaments?

Answer 20

Stretch Pudendal nerve
 - neuropraxia & muscle weakness
Stretch & damage pelvic floor & perineal muscles
Stretch/rupture ligament supports
 - Ineffective muscle action

Question 21

What treatments are there for pelvic floor dysfunction?

Answer 21

Pelvic floor muscle exercises (also prophylactic)
Continence surgeries
Prolapse procedures (replace organs, restore supports)