Anatomy of UI & prolapse

Question 1

What does the pelvic floor separate?

Answer 1

It separates the pelvic cavity (above) from the perineum (below)

Question 2

What are the important functions of the pelvic floor?

Answer 2

It supports the pelvic organs and also helps maintain urinary & faecal continence

Question 3

Name the 3 layers of the pelvic floor from (deepest to most superficial)

Answer 3

1. Pelvic diaphragm
2. Muscles of perineal pouches
3. Perineal membrane

Question 4

The pelvic diaphragm is the deepest layer of the pelvic floor, what is it comprised of ?

Answer 4

2 main muscle groups:

1. Levator ani
2. Coccygeus

Note the pelvic diaphragm has the appearance of a sling

Question 5

What are the 2 holes of significance in the pelvic floor and why

Answer 5

There are 2 ‘holes’ of significance to allow for urination and defacation

1. Urogenital hiatus - situated anterioly & in between the medial borders of the levator ani muscles, it allows passage of the urethra (& vagina in females)
2. Rectal hiatus - a centrally positioned gap which allows passage of the anal canal

Question 6

What is situated between the urogenital hiatus and the anal canal ?

Answer 6

The perineal body - it joins the pelvic floor to the perineum

Question 7

Which of the 2 groups of muscles makes up the majority of the pelvic diaphragm?

Answer 7

The levator ani

Question 8

What 3 muscles make up the levator ani muscle ?

Answer 8

1. Puborectalis - U shaped sling which extends from the pubic bone, past the urogenital hiatus & around the anal canal (it is thick & chunky)
2. Pubococcygeus - arises from the pubic bone & ant. aspect of the tendinous arch to attach at the coccyx (appears wide & thin)
3. Iliococcygeus - arsies from ischial spines & ant. aspect of tendinous arch to attach at the coccyx

Note in the pic the other main muscle not labelled is the coccygeus muscle

Tendinous arch = thickened fascia of the obturator internus muscle

Question 9

Go over the osteology of the pelvis

Answer 9

Question 10

What is the normal disposition of the levator ani muscles and when/why does this change

Answer 10

They are normally tonically contracted except when they need to relax to allow urination & defacation

Question 11

What is the innervation of the levator ani muscles

Answer 11

The peudendal nerve (S2-4) & the nerve to the levator ani (S3-5)

Question 12

What are the origin and insertion points of the coccygeus muscle

Answer 12

It originates from the ischial spines & attaches to the lateral aspect of the sacrum & coccyx

Question 13

What is the innervation of the coccygeus muscle ?

Answer 13

Innervated by ant. rami of S4&5

Question 14

What provides additional support to the pelvic organs (alongside the pelvic floor)?

Answer 14

Ligaments & endo-pelvic fascia

Question 15

Describe what the endo-pelvic fascia is

Answer 15

This is connective tissue which is almost like packaging around the pelvic organs, it provides some support but mainly allows room for pelvic organs to expand

Question 16

List the different pelvic ligaments

Answer 16

• Utero-sacral
• Transverse cervical (most important)
• Lateral ligament of the bladder
• Lateral rectal ligaments (not in pic, so they travel from lateral aspect of rectum up towards the sacrum)

Question 17

What can the perinal pouches be divided into ?

Answer 17

There is the deep & the superficial perineal pouches

Question 18

Describe the location of the deep perineal pouch

Answer 18

It is located below the fascia ocvering the inferior aspect of the pelvic diaphragm & lies superior to the perineal membrane

(so it goes pelvic diaphragm → inf. aspect of covered by fascia → deep perineal pouch)

Note: Think of it in terms of standing up

Question 19

What is contained within the deep perineal pouch ?

Answer 19

• Part of the urethra (& vagina in females)
• Bulbourethral gland in males
• neurovascular bundle for penis/clitoris
• External urethral sphincter
• Extension of ischioanal fat pads & muscles

Question 20

What muscles are contained in the deep perineal pouch and state their function

Answer 20

• Compressor urethrae - functions to compress the urethra
• External urethral sphincter
• Deep transverse perineal muscle (contained bulbourethral gland in males)

Question 21

What is the difference between the deep transverse perineal muscle in males and females ?

Answer 21

It is smooth muscle in females & skeletal in males

Question 22

What is the function of the deep transverse perineal muscle?

Answer 22

• To help expel the last drops of urine (additionally explusion of semen in males)
• Since it is a pelvic floor muscle it will also contribute to supporting the pelvic organs

Question 23

Where is the perineal membrane located ?

Answer 23

Superficial to the deep perineal pouch

Question 24

What is the perineal membrane and what is its attachments ?

Answer 24

It is a thin sheet of tough, deep fascia which attaches laterally to the sides of the pubic arch, closing the urogenital triangle

Question 25

What openings are found in the perineal membrane ?

Answer 25

Opening for the urethra (& vagina in females)

Question 26

What together with the perineal body is the last passive support of the pelvic organs ?

Answer 26

The perineal membrane

Question 27

Go over this pic to appreciate the layers of the pelvic floor Note that it is looking from above down on the pelvic floor so you are seeing the pelvic diaphragm first (the deepest anatomically)

Answer 27

Question 28

Where is the superfifical perineal pouch located ?

Answer 28

It lies inferior to the perineal membrane

Question 29

What does the superficial perineal pouch in males contain?

Answer 29

* The root of the penis and its associated muscles * Also contains proximal spongy (penile) urethra, superficial transverse perineal muscle and branches of internal pudendal vessels and pudendal nerve

Question 30

What is the root of the penis comprised of and what are its associated muscles ?

Answer 30

Root of the penis is comprised of (erectile tissue): 1. The bulb containing corpus spongiosum 2. The cura cotaining corpus cavernosum The bulb is then covered bulbospongisus muscle The cura is then covered by ischiocavernosus muscle

Question 31

What is contained within the superficial perineal pouch in females ?

Answer 31

* Contains female erectile tissue and associated muscle * Also contains greater vestibular glands, superficial transverse perineal muscle and branches of internal pudendal vessels and pudendal nerve

Question 32

What is the erectile tissue and associated muscles found in the superficial perineal pouch in females ?

Answer 32

* The cura which then join together in the midline to form the clitoris * Bulbs (2 in females unlike 1 in males) at the base of the bulbs are the greater vestibular glands (bartholins glands) Clitoris & cura is covered by the ischiocavernosus muscle. Bulbs are coevered by the bulbospongiosus muscle

Question 33

What is the function of the greater vestibular glands ?

Answer 33

To secrete mucus into the vagina to lubricate it

Question 34

The muscles in the female superficial perineal pouch are much less developed than those in the males - T or F and give reasoning

Answer 34

True - because the male muscles need to be more developed to permit erections & ejaculation

Question 35

List from deep to superficial the layers of the pelvic floor

Answer 35

1. Levator ani 2. Deep perineal pouch 3. Perineal membrane 4. Superficial perineal pouch

Question 36

Where is the perineal body located ?

Answer 36

It is located at the junction of the urogenital & anal triangle - the central point of the perineum, it lies just deep to the skin

Question 37

What is the function of the perineal body ?

Answer 37

* It acts as a point of attachment for muscle fibres from the pelvic floor & perineum. * It is also key in support of the pelvic floor * It acts as a tear resistant body between vagina & external anal sphincter supporting the post. part of vaginal wall against prolapses (in males it lies between the bulb of the penis & the anus)

Question 38

What are the 2 main functions of the pelvic floor ?

Answer 38

1. Provides support to the pelvic organs 2. Helps maintain continence

Question 39

How does the pelvic floor provide support to the pelvic organs ?

Answer 39

* It is normally tonically contracted to provide support. It also actively contracts anytime you raise intra-abdo pressure due to e.g. coughing, sneezing, vomiting * They relax to allow urination & defacation

Question 40

What muscles from the pelvic are specifically involved in maintaining continence ?

Answer 40

* **Urinary;** external urethral sphincter, compressor urethrae & levator ani * **Faecal;** tonic contraction of puborectalis which bends the anorectum anteriorly, active contraction then maintains contience after rectal filling

Question 41

What are the causes of injury to the pelvic floor ?

Answer 41

* **Pregnancy** * **Childbirth; stretching/tearing or pudendal nerve damage can all occur** * Chronic constipation * Obesity * Heavy lifting (e.g. body builders could be predisposed) * Chronic cough or sneeze * Previous injury to pelvis/pelvic floor * Menopause

Question 42

What does urinary continence depend on ?

Answer 42

* Urinary bladder neck support * External urethral sphincter * Smooth muscle in urethral wall