Perineum

Question 1

what are the main muscles of the perineum?

Answer 1

bulbospongiosus 
ischiocavernosus 
superficial transverse perineal 
deep transverse perineal 
external anal sphincter

Question 2

what makes up the border in the perineum ?

Answer 2

ischial tuberosity
pubic symphysis
coccyx

Question 3

what are the 2 triangles of the perineum?

Answer 3

anal triangle

urogenital triangle

Question 4

what is the name of the fascia which stretches between right and left sides of the pubic arch?

Answer 4

deep perineal fascia

Question 5

what is the innervation of the bulbospongiosus?

Answer 5

muscular branch of perineal nerve, branch of the pudendal nerve (S2-S4)

Question 6

what is the function of the bulbospongiosus muscle?

Answer 6

supports and fixes perineal body/pelvic floor
compresses bulb of penis to expel last drops of urine and semen
assists in the erection of the clitoris

Question 7

what is the innervation of the external anal sphincter?

Answer 7

branch of pudendal nerve (S2-S4)

Question 8

what is the function of the external anal sphincter?

Answer 8

constricts anal canal during peristalsis and maintains continence
supports and fixes perineal bod/pelvic floor

Question 9

what is the innervation of the ischiocavernosus muscle?

Answer 9

muscular branch of perineal nerve, branch of pudendal (S2-S4)

Question 10

what is the function of the ischiocavernosus muscle?

Answer 10

maintains erection of the penis in males

Question 11

what is the innervation of the superficial transverse perineal?

Answer 11

branch of pudendal nerve (S2-S4)

Question 12

what is the function of the superficial transverse perineal?

Answer 12

support and fix perineal body to support abdomen-pelvic viscera and resist increased intra abdominal pressure

Question 13

what is the innervation of the external urethral sphincter?

Answer 13

branch of pudendal nerve (S2-S4)

Question 14

what is the function of the external urethral sphincter?

Answer 14

compresses urethra to maintain urinary continence

Question 15

what is the perineal body?

Answer 15

fibromuscular structure located in the midline of the perineum
it is the final support of the perineum

Question 16

what is the clinical significance of the perineal body?

Answer 16

central attachment of perineal muscles and functions to support pelvic floor

Question 17

what muscles converge towards the perineal body?

Answer 17

bulbospongiosus
superficial transverse perineal
deep transverse perineal
external anal sphincter

Question 18

what are the superficial and deep perineal pouches and what is their clinical significance?

Answer 18

fascial limited potential spaces transversed by the urethra

they may become infiltrated with urine following traumatic or surgical injury of the urethra

Question 19

what is the external urethral sphincters innervation?

Answer 19

pudendal nerve S2-S4

Question 20

what is the innervation of the internal urethral sphincter?

Answer 20

sympathetic T10-L2

Question 21

is the external urethral sphincter located in the superficial or deep perineal pouches?

Answer 21

superficial perineal pouch

Question 22

what muscle does the deep perineal pouch surround?

Answer 22

deep transverse perineal muscle

Question 23

what are the 3 parts of the male urethra?

Answer 23

prostatic
membranous
penile/spongy

Question 24

what is the tissue which surrounds the penile urethra called?

Answer 24

corpora cavernosa

Question 25

what are the narrowest and widest parts of the male urethra?

Answer 25

narrowest - membranous as it passes through the external urethral sphincter widest - penile

Question 26

what is the major content of the ischio-anal fossae?

Answer 26

fat

Question 27

why is the ischia-anal fossae often a site of abscess formation ?

Answer 27

often several fistulous tracks end in the fatty tissue

Question 28

what are common causes of ischia-anal abscesses?

Answer 28

STI, crohns, blocked anal gland, infected anal canal | presentation is fullness and tenderness between anal tuberosity

Question 29

through which foramen does the pudendal nerve pass through to reach the ischia-anal fossae?

Answer 29

lesser sciatic foramen

Question 30

what vessels are present within the ischio-anal fossae?

Answer 30

pudendal nerve | obturator internus nerve

Question 31

what structures does the pudendal nerve innervate?

Answer 31

muscles of the perineum | levitator ani muscles of the pelvic floor

Question 32

what is the course of the internal pudendal artery?

Answer 32

branch of internal illiac | goes out through greater sciatic and around sacrospinous ligament then back in through the lesser sciatic foramen

Question 33

what are the main branches of the internal iliac artery?

Answer 33

greater and lesser gluteal arteries internal pudendal artery obturator artery

Question 34

what is the innervation of the external urethral sphincter?

Answer 34

somatic via pudendal nerve

Question 35

what is the innervation of the internal urethral sphincter?

Answer 35

sympathetic - T10-L2 via hypogastric | parasympathetic - S2-S4 via pelvic nerves

Question 36

what is the blood and nerve supply of the prostate and seminal vesicles?

Answer 36

sympathetic L1-L2 via hypogastric | superior and inferior vesical artery

Question 37

what is the function of the puborectalis muscle?

Answer 37

maintains faecal continence by creating a U shaped sling aound the anorectum

Question 38

what is the blood supply for the rectum?

Answer 38

above the pectinate line: superior rectal artery (branch of inferior mesenteric artery) below pectinate line: inferior rectal artery (branch of the internal pudendal artery)

Question 39

what is the neurovascucular supply of the rectum?

Answer 39

superior to the pectinate line: inferior hypogastric plexus inferior to the pectinate line: inferior anal nerves from the pudendal nerve