Lecture 21 - perineum: anal triangle

Question 1

What ia the perineum/

Answer 1

region below the pelvic floor - between the thighs

Question 2

it has the same diamond shaped boundaries as the …

Answer 2

pelvic outlet:
differently organised

horizontal between the ishail tuberosities -

Question 3

what are the two triangles created?

Answer 3

urogenital and anal

Question 4

what are the boundaries of the perineum?

Answer 4

symphysis pubic on top

ishail tuberosities on each side

coccyx at the bottom

Question 5

The urogenital triangle is further subdivided into a..

What divides them?

Answer 5

superificial and deep (close to pelvic floor)

divided by the peroneal membrane

Question 6

peroneal membrane has a free _____ edge

Answer 6

posterior

Question 7

the superifical part of the peroneal membrane is the anchor point for…

Answer 7

the external genitalia

Question 8

the deep surface of the peroneal membrane is a muscular diaphragm made up of the ______

Answer 8

sphincters of the tubular structures

Question 9

The free posterior edge of the peroneal membrane is reinforced by muscles called

Answer 9

superifical transverse perineal msucle

deep transverse erineal muscles

(mirrored)

Question 10

What is the name of the fat filled space between the ishium and anal canal?

Answer 10

ishiorectal fossa

Question 11

The side wall of the perineum is the inferior half of …

Answer 11

obturator internus (below the linear attachment of levator ani)

Question 12

Where does the NV bundle of the perineum run?

Answer 12

the pudendal canal - in the fascia overlying obturator internus

Question 13

There is angulation of rectum/anal canal is….

hat maintains it?

Answer 13

downwards and backwards

created by puborectalis

Question 14

The upper 2/3 of the anal canal is lined by ..

and supplied by…

Answer 14

mucosa -

Sup. rectal artery
veins draining to the portal system

Question 15

The upper 2/3 of the anal canal is innervated by -

Answer 15

autonomic nerves

Question 16

what delineates the upper 2/3 from lower part of anal canal

Answer 16

pectinate line -

Question 17

the lower 1/3 of the anal canal is arterial supplied by

Answer 17

inferior rectal artery - branch of iliac system

drains to systemic veins

Question 18

true or false

there is a porto-systemic anastomosis at the anal canal

Answer 18

true

the venous plexus can become engorged

Question 19

the lower 1/3 of the anal canal is innervated by

Answer 19

somatic nerves

inf. rectal branch of pudendal nerve

Question 20

describe the internal anal sphinter

Answer 20

thickening in smooth muscle wall - autonomic control

Question 21

describe the external anal sphinter

Answer 21

3 components

deep
superficial
subcutaneous

Question 22

The deep component of the external anal sphincter fuses with..

Answer 22

puborectalis - at the ano-rectal junction

Question 23

The superficial component of the external anal sphincter is fixed anteriorly and psoteriorly to what?

Answer 23

posteriorly: tip of the coccyx
anteriorly: a fibrous thickening of the free posterior border of the perineal membrane called the perineal body - also called a central tendon

Question 24

what mscles are connected to the central tendon or perineal body?

Answer 24

sup and deep transverse perineal muscle

superfiical component of the ext. anal sphincter

levator ani

all of the perineal sphincter assoc. with the vagina

Question 25

the female urethra is very short typcially how long?

Answer 25

4cm

Question 26

what does the female urethra pass?

Answer 26

pelvic floor

deep perineal pouch - part deep to the membrane

perineal membrane

vestibule

exterior

Question 27

the external urethral shpincter in females is __ to the perineal membrane

Answer 27

deep

Question 28

The pair of paraurethral (mucus) glands are either side of the urethra are situated _____ to the perineal membrane

Answer 28

superficial

Question 29

what are the adv/disadv. of the short urethra in females?

Answer 29

advantages

catherising is wayyy easier

disadvantages

any sup pathogens are close to the bladder= urinary tract infection

Question 30

What are the four parts of the male urethra’s journey?

Answer 30

1. preprostatic - very short, at the bladder neck
2. prostatic part - traverses the prostate (3cm)
3. membranous - traverses the perineal membrane, perineal pouch
4. spongy/penile part

Question 31

The bulbourethral gland’s ducts open into the ___ part of the urethra

Answer 31

penile

Question 32

describe the urethral sphincters in male

Answer 32

internal - assoc with bladder neck

external - assoc. with deep pouch of perineal membrane (with all the other sphincters) - same with female

Question 33

Descibe the root of the penis

what are the anchor points?

Answer 33

midline structure - corpus spongiosum (attached to the sup. surface of the perineal membrane)

pair of erectile cylinders - corpora cavernosa - achored to the ishiopubic rami

Question 34

what are the respective muscles the proximally ocver the roots of the penis?

Answer 34

ishiocavernosis and bulbo spongiosis

Question 35

The female has two ____ ______ either side of the perineal membrane

Answer 35

corpro caverosa

Question 36

The midline erectile mass of the female is ___

Answer 36

paired