Session 5 - Male pelvis and perineum

Question 1

In the male and female pelvis:

what are the differences in the pelvic inlet?

Answer 1

female = oval/round
male = narrow/heart-shaped

Question 2

In the male and female pelvis:

what are the differences in the sub pubic angle?

Answer 2

female = round >80 degrees
male = narrow 50-60 degrees

Question 3

In the male and female pelvis:

what are the differences in the ischial spines?

Answer 3

project medially in males and not in females

Question 4

In the male and female pelvis:

what are the differences in the greater/false pelvis?

Answer 4

in females it is shallow and in males it is deep

Question 5

In the male and female pelvis:

what are the differences in the lesser/true pelvis?

Answer 5

females = wide, shallow and cylindrical
males = narrow, deep and tapering

Question 6

What is the X:Y ratio in the male and female pelvis?

X = distance between the pubic symphysis and the anterior margin of the acetabulum
Y = the diameter of the acetabulum

Answer 6

females - 1 or >1

males - less than 1

Question 7

What is the caecum?

Answer 7

a short, pouch-like region of the large intestine between the ascending colon and vermiform appendix (connected to the junction of the small and large intestines)

Question 8

What are the seminal vesicles?

Answer 8

a pair of simple tubular glands posteroinferior to the urinary bladder of some male mammals. They secrete fluid that partly composes the semen.

Question 9

Which or the 2 bends of the male urethra can be straightened before passing a catheter?

Answer 9

the second one - the one that is close to the glanjsof the penis
the one closer to the bulb of the penis cannot be straightened

Question 10

Give an overview of the course of the ductus deferens

Answer 10

passes from the testes —–> inguinal canal —–> over and behind the urethra —–> through the prostate

Question 11

Where do the seminiferous vesicles open into?

Answer 11

into the ducts deferens between the ampulla and the ejaculatory duct

Question 12

Where are the bulbourethral glands?

Answer 12

(posterior and lateral to the membranous portion of the urethra at the base of the penis)
between the two layers of the fascia of the urogenital diaphragm, in the deep perineal pouch.

Question 13

What are the two layers of the fascia of the urogenital diaphragm?

Answer 13

superior and inferior fascia surround the internal sphincter (splinter urethrae)

Question 14

What is the purpose of the internal urethral sphincter?

Answer 14

prevents semen passing up from the prostate to the bladder during ejaculation
(NOT to stop urine passing through)

Question 15

Give the names of the opening that can be found at the prostatic urethra, where the urinary and reproductive tracts meet

Which opening can cause complications during catheterisation?

Answer 15

• openings of the prostate gland
• openings of the ejaculatory ducts (seminal gland secretions and sperm)
• prostatic utricle (a cul-de-sac) - the tip of the catheter can become lodged here

Question 16

What is the perineum?

Answer 16

the diamond shape area between the pubic symphysis, ischial tuberosities and coccyx

divided into anterior (urogenital) and posterior (anal) triangles

(LA: the diamond shaped areas between the thighs when the person sides on the back with thighs flexed and abducted)

Question 17

Describe the anterior triangle of the perineum

Answer 17

‘the urogenital triangle’

divided into superficial and deep paths/pouches by the perineal membrane

Question 18

Describe the posterior triangle of the perineum

Answer 18

‘the anal triangle’

there is ischio-anal fossae - fat filled spaces operating the anal canal and elevator and from the pelvic wall

Question 19

Where is the deep perineal space?

Answer 19

above the PM and below the fascia of the pelvic membrane

Question 20

Where is the superficial perineal space?

Answer 20

below the PM and perineal fascia

Question 21

What are the deep and superficial perineal spaces?

Answer 21

potential spaces that only become real when fluid leaks into them

Question 22

What are the contents of the superficial perineal pouch in males?

Answer 22

contains the erectile tissues that form the penis and clitoris, and three muscles – the ischiocavernosus, bulbospongiosus and superficial transverse perineal muscles

Question 23

What are the erectile tissues of the superficial perineal pouch on males?

Answer 23

• corpus spongiosum - median erectile tissue mass - bulb of the penis
• corpora caveronosae - lateral erectile tissue - attached to the ischiopubic rami (paired muscles)
  (3 erectile tissue masses altogether)

they meet and form the shaft and head of the penis (or clitoris in females)

Question 24

How do the erectile tissue of the superficial perineal pouch differ in females?

Answer 24

the corpus spongiosum divides around the vestibule to form vestibular bulbs

the corpus spongiosum and corpora caveronosae meet and form the clitoris (not the penis)

Question 25

What are the contents of the deep perineal pouch in males?

Answer 25

(contains part of the urethra) external urethral sphincter, the bulbourethral glands and the deep transverse perineal muscles

Question 26

What is the spermatic cord?

Answer 26

a collection of vessels, nerves and ducts that run to and from the testes
the cord-like structure in males formed by the vas deferens and surrounding tissue that runs from the deep inguinal ring down to each testicle

Question 27

Where is the spermatic cord formed and where does it go to?

Answer 27

formed at the opening of the inguinal canal (the deep inguinal ring)

The cord passes through the inguinal canal, entering the scrotum via the superficial inguinal ring. It continues into the scrotum, ending at the posterior border of the testes.

Question 28

What are the 2 fascial layers surrounding the spermatic cord?

Answer 28

External spermatic fascia
Cremaster muscle and fascia
Internal spermatic fascia

Question 29

Where is the testes are the spermatozoa stored until ejaculation?

Answer 29

the body of the epididymis

Question 30

Describe the structure of the penis

Answer 30

• corpus spongiosum contains the urethra
• corpus cavernosum (paired) - this stop just before the glans
• the glans is part of the spongiosum

Question 31

What are the artery branches supplying the cavernous spaces (that are usually coiled)?

Answer 31

helicine arteries

Question 32

Summarise the nerves of the pelvis and perineum

Answer 32

pelvic sympathetic: T10-L2 via hypogastric plexus
pelvis parasympathetic: S2-S4
perineum - pudendal nerve S2-S4