Repro: The Pelvic Floor

Question 1

What is the pelvic floor?

Answer 1

A muscular and fibrous diaphragm that fills the lower part of the bony pelvis and supports the pelvic organs
It separates the pelvic cavity from the inferior perineum (where the genitalia and anus are)

Question 2

What are the nerve routes supplying the pelvic floor?

Answer 2

Sacral plexus - S 2 3 4 keeps the rectum off the floor

Question 3

What lies above the posterior fornix of the vagina?

How is this useful clinically?

Answer 3

The pouch of douglas - can be used for culdocentesis (drawing fluid from the peritoneum)

Question 4

What is the urogenital hiatus?

Answer 4

A gap in the anterior of the pelvic floor that allows the urethra and vagina to pass through

Question 5

What is the rectal hiatus?

Answer 5

A gap in the central pelvic floor which allows the anal canal to pass through

Question 6

What is the function of the pelvic floor?

Answer 6

• support the abdominal and pelvic organs
• resist against increased in pelvic and abdominal pressure during coughing or lifting
• urinary and fecal continence, the muscle fibres have sphincter actions

Question 7

List the 3 components that are up the pelvic floor

Answer 7

• the levator ani muscles (largest component)
• the coccygeus muscle
• fascial coverings of the muscles

Question 8

What are the paired muscles making up the levator ani muscle?

Answer 8

The pubococcygeus
The puborectalis
The iliococcygeus

Question 9

What is the innervation of the levator ani?

Answer 9

Branches of the pudendal nerve S234

Question 10

What are the attachments of the levator ani?

Answer 10

Anterior - the pubic bodies
Laterally - the thickened fascia of the obturator internus muscle (called the tendinous arch)
Posteriorly - the ischial spines

Question 11

What is the main function of the puborectalis?

Answer 11

Its a thick muscle that maintains faecal continence

Question 12

What is the innervation of the coccygeus?

Answer 12

Anterior rami of S4 and S5

Question 13

What are the attachments of the coccygeus?

Answer 13

Originates from the ischial spines and travels to lateral aspects of sacrum and coccyx via the sacrospinous ligament

Question 14

What are the surface borders of the perineum?

Answer 14

Anteriorly the mons pubis/ base of penis
Laterally the medial surface of the thighs
Posterior the superior end of the intergluteal cleft

Question 15

What 2 triangles can the perineum be split into?

Answer 15

An imaginary line between the ischial tuberosities forms the anterior urogenital and posterior anal triangles

Question 16

What are the components of the anal triangle?

Answer 16

The anal aperture (opening)
The external anal sphincter
2 ischioanal fossae which are spaces located laterally to the anus that contain fat and connective tissue, allowing the anal canal to expand

Question 17

What are the deep and superficial perineal pouches?

Located in the urogenital triangle

Answer 17

The deep perineal pouch is a potential space between the pelvic floor and the perineal membrane. It contains part of urethra and external urethral sphincter (and bulbourethral glands in males).
The superficial perineal pouch is a potential space between the perineal membrane and the perineal fascia. It contains the erectile tissue of the penis and clitoris, bartholians glands and 3 muscles - ischiocavernosus, bulbospongiosus and superficial transverse perineal muscles.

Question 18

What is the perineal membrane? (Located in the urogenital triangle)

Answer 18

A layer of tough fascia which provides attachment for the muscles of the superficial external genitalia and helps to support pelvic viscera

Question 19

What is the deep and superficial perineal fascia? (Located in the urogenital triangle)

Answer 19

Deep fascia covers the superficial perineal muscles
Superficial fascia is continuous with the superficial fascia of the abdo wall. Can be divided into 2 - the superficial layer is fatty and forms the labia majora and mons pubis

Question 20

What is the perineal body?

Answer 20

An irregular and fibromuscular mass - it is the central point of the perineum.
Contains skeletal muscle, smooth muscle, collagen and elastic fibres

Question 21

List the muscles which attach to the perineal body

Answer 21

• levator ani
• bulbospongiosus
• superficial and deep transverse perineal muscles
• external anal sphincter
• external urethral sphincter

Question 22

What is the innervation to the perineal body?

Answer 22

Pudendal nerve S 234

Question 23

What is the arterial supply to the perineal body?

Answer 23

Internal pudendal artery

Question 24

What are bartholin’s gland cysts?

Answer 24

The ducts can become blocked causing the glands to swell and for fluid-filled cysts. They can become infected and inflamed - bartholinitis.
Most commonly caused by infection from bacteria such as E coli or staph

Question 25

During childbirth which nerves and muscles are at highest risk of injury?

Answer 25

The levator ani muscles (particularly pubococcygeus and puborectalis as these are most medial) and pudendal nerve

Question 26

What can cause prolapse of the pelvic viscera (bladder and vagina)?

Answer 26

If there is trauma to the pelvic floor or the muscles have poor tone

Question 27

What is the purpose of an episiotomy?

Answer 27

A surgical cut to the perineum during childbirth to prevent uncontrolled tearing of the perineal muscles (this can lead to rectal herniation)

Question 28

What risk factors increase the chance of prolapse?

Answer 28

- age - number of vaginal deliveries - family history of pelvic floor dysfunction - weight - chronic coughing