Lecture 26: Male and Female Perineum

Question 1

What does the perineum contain?

Answer 1

External genitalia and anal canal

Question 2

What is the anterior boundary of the perineum?

Answer 2

Pubic symphysis

Question 3

What is the posterior boundary of the perineum?

Answer 3

Coccyx

Question 4

What is the anterolateral boundary of the perineum?

Answer 4

Ischiopubic ramus

Question 5

What is the posterolateral boundary of the perineum?

Answer 5

Sacrotuberous ligament

Question 6

What is the superior boundary of the perineum?

Answer 6

Pelvic diaphragm (levator ani muscles)

Question 7

What is the inferior boundary of the perineum?

Answer 7

Skin associated with external genitalia and anal canal

Question 8

Two triangles can be created in the perineum. Where is that imaginary line between?

Answer 8

From each ischial tuberosity

Question 9

What are the two triangles of the perineum?

Answer 9

Anterior: urogenital triangle

• urethra
• external genitalia

Posterior: anal triangle

• anal canal
• anus

Question 10

What is found in the anal triangle?

Answer 10

External anal sphincter: distal third
-ectoderm

Internal anal sphincter: proximal two-thirds
-endoderm

Question 11

What separates the external and internal anal sphincter?

Answer 11

Pectinate line

Question 12

What is the lateral boundary of the ischiorectal fossa?

Answer 12

Obturator internus muscle

Ischium

Question 13

What is the superomedial boundary of the ischiorectal fossa?

Answer 13

Pelvic Diaphragm: Levator ani muscle + external anal sphincter

Question 14

What makes up the base of the ischiorectal fossa?

Answer 14

Skin of perineum

Question 15

Where is the pudendal canal located?

Answer 15

Medial surface of Obturator internus muscle

Question 16

What does the pudendal canal contain?

Answer 16

Pudendal nerve
Internal Pudendal artery
Internal Pudendal vein

Question 17

What does the pudendal nerve do?

Answer 17

• Carries sensation from the external genitalia of both sexes and the skin around the anus and perineum
• Motor supply to male or female external urethral sphincters and external anal sphincter

Question 18

The inferior rectal artery is a branch from where?

Answer 18

Inferior pudendal artery

Question 19

The inferior rectal nerve is a branch from where?

Answer 19

Pudendal nerve

-supplies anal sphincters and skin

Question 20

What are the two spaces found in the urogenital triangle?

Answer 20

1. Superficial perineal space

2. Deep perineal space

Question 21

What is found in the deep perineal space in males?

Answer 21

1. Superior fascia
2. Inferior fascia/perineal membrane
3. Deep transverse perineal muscle
4. External urethral sphincter
5. Membranous urethra
6. Bulbourethral glands

Question 22

What is found in the deep perineal space in females?

Answer 22

1. Superior fascia
2. Inferior fascia/perineal membrane
3. Deep transverse perineal muscle
4. External urethral sphincter
5. Compressor urethrae
6. Vagina

Question 23

What is found in the superficial perineal space in males?

Answer 23

1. Root of penis
2. Ischiocavernosus muscle
3. Bulbospongiosus muscle
4. Penile urethra
5. Superficial transverse perineal muscle

Question 24

What is found in the body of the penis?

Answer 24

1. Skin
2. Subcutaneous tissue
3. Corpus spongiosum (penile urethra)
4. Corpus cavernosum
5. Dorsal artery, vein, and nerve

Question 25

What is found in the superficial perineal space in females?

Answer 25

1. Bulbs of vestibule 2. Bulbospongiosus muscle 3. Greater vestibular glands 4. Superficial transverse perineal muscle 5. Clitoris 6. Ischiocavernosus muscle

Question 26

What does the external pudendal artery supply?

Answer 26

Males: scrotum and penis Females: labia majora and clitoris

Question 27

What does the internal pudendal artery supply?

Answer 27

Perineal structures

Question 28

What are the branches of the pudendal nerve?

Answer 28

1) Inferior rectal nerve: anal skin and external anal sphincter 2) Perineal nerve 3) Dorsal nerve: penis/clitoris

Question 29

What do the superficial inguinal nodes drain?

Answer 29

1. Superficial perineal space 2. Distal portions of vagina and anal canal - inferior to pectinate line

Question 30

What do the deep inguinal nodes drain?

Answer 30

1. Deep perineal space 2. Proximal portions of vagina and anal canal - superior to pectinate line

Question 31

What is an episiotomy?

Answer 31

Incision between vagina and anus to prevent perineal tear