ANATOMY OF PELVIS ANORECTUM AND PERITONEUM

Question 1

What are the two parts of the pelvis

Answer 1

false/greater and true/lesser pelvis

Question 2

what makes up the false pelvis

Answer 2

from the iliac crest to pubic symphysis

Question 3

what makes up the true pelvis

Answer 3

pubic symphysis to the sacrum

Question 4

what is the pelvic floor and pelvic outlet made of

Answer 4

pelvic floor is muscles and ligaments and the pelvic outlet is formed by the perineum

Question 5

where do the perineal membrane lie

Answer 5

inferiorly to the anterior part of the pelvic floor

Question 6

what three ligaments attach to the pelvic wall

Answer 6

sacrospinous ligament
sacrotuberous ligament
obturator membrane (the circular part)

Question 7

what is the function of the ligaments

Answer 7

stabilize the sacrum to the pelvis and keeps it in line

Question 8

what are apertures

Answer 8

tiny holes or openings

Question 9

what does the sacrospinous ligament divide

Answer 9

the sciatic foramen into a greater one superiorly and a lesser one inferiorly

Question 10

what aperture does the obturator membrane cause

Answer 10

obturator canal

Question 11

what two muscles are part of the lateral pelvic wall

Answer 11

piriformis and obturator internus

Question 12

where does the piriformis attach

Answer 12

from the sacrum through the greater sciatic foramen to the greater trochanter of the femur

Question 13

what nerves innervate the piriformis

Answer 13

brnaches from S1 and S2

Question 14

what is the function of the piriformis

Answer 14

laterally rotates the hip joint and abducts the hip

Question 15

where does the obturator muscle attach

Answer 15

to the obturator and surrounding bone ( looks like a fan)

Question 16

which nerves innervate the obturator internus

Answer 16

from L5 and S1

Question 17

what is the function of the obturator internus

Answer 17

laterally rotates the hip joint anf abducts the hip

Question 18

what muscle is part of the inferolateral part of the pelvic wall

Answer 18

ischiococcygeus/coccygeus

Question 19

where does the ischiococcygeus attach

Answer 19

from ischial spine to the coccyx

Question 20

which nerve innervates the ischiococcygeus

Answer 20

S3 and S4

Question 21

what is the function of ischiococcygeus

Answer 21

pulls the coccyx forward after defecation

Question 22

what muscles make up the pelvic floor

Answer 22

levator ani muscles

Question 23

what are the levator ani muscles

Answer 23

muscle pairs which originate from each pelvic wall and meet in the middle

Question 24

what are the two openings in the levator ani muscles

Answer 24

urogenital hiatus - passage for urethra and vagina

rectal hiatus - passage for anal canal

Question 25

what structure do the levator ani muscles cover

Answer 25

the lesser sciatic foramen

Question 26

what three muscles make up the levator ani

Answer 26

pubococcygeus puborectalis iliococcygeus

Question 27

what nerves innervate the levator ani

Answer 27

anterior rami of S4 | pudendal nerve S2-S4

Question 28

what is the main muscle involved in defecation

Answer 28

puborectalis

Question 29

what happens to the anorectal angle and puborectalis during continence (resting)

Answer 29

the anorectal angle is maintained | contraction of puborectalis

Question 30

what happens to the anorectal angle and puborectalis during defecation

Answer 30

the anorectal angle straightens | relaxation of puborectalis

Question 31

what two structures of the perineal pouch are common in both males and females

Answer 31

external urethral sphincter and deep transverse perineal muscles

Question 32

what two muscles do women have in the perineal pouch and what do they do

Answer 32

sphincter urethrovaginalis compressor urethrae facilitate the closing of the urethra

Question 33

where is the sphincter urethrovaginalis

Answer 33

surrounds the urethra and vaginal hiatus

Question 34

where is the compressor urethrae

Answer 34

from ischiopubic rami to the urethra

Question 35

what nerve innervates the perineal pouch

Answer 35

pudenal nerve S2 to S4

Question 36

what muscle forms the perineal body

Answer 36

deep transverse perineal muscles

Question 37

what are two shared structure/fold in the peritoneum common to both males and females

Answer 37

median umbilical fold | medial umbilical fold

Question 38

what part the rectum is not covered/partially covered by the peritoneum

Answer 38

middle third partly | lower third not

Question 39

where are the median and medial umbilical folds

Answer 39

the medial one is more superior than the median

Question 40

what are two pouches found in the peritoneum of women

Answer 40

vesico-uterine | recto-uterine (pouch of douglas)

Question 41

what pouch is found in the peritoneum of males

Answer 41

rectovesical

Question 42

what are fascia lines

Answer 42

they cover the pelvic walls and cavity forming sheaths around vessels and nerves

Question 43

what are the two types of fascia in males

Answer 43

prostatic fascia | retrovesical septum

Question 44

where does the rectum extend from

Answer 44

from the sigmoid colon at S3. ends as it passes through elevator ani. Stops 15cm from the anal orifice

Question 45

what are the three lateral curves in the rectum

Answer 45

curves right at the upper part curves really left in middle curves right at the end

Question 46

what are the 2 semi lunar transverse folds

Answer 46

mucosa which is circular and longitudinal muscle - can see it externally devoid of longitudinal muscle

Question 47

which direction does the rectum move in relation to the sacrum

Answer 47

posteriorly in concavity with the sacrum then curves anteriorly

Question 48

what is the anorectal flexure

Answer 48

when the rectum curves from anterior to posterior

Question 49

where is the anorectal flexure in males and females

Answer 49

in males its at the level of the prostate and in females its slightly below the coccyx

Question 50

what landmark can it be used to palpate in females

Answer 50

he posterior all of the vagina and cervix

Question 51

where does the anal canal begin

Answer 51

at the end of the rectal ampulla

Question 52

what is the pectineal line

Answer 52

divides the anus into upper and lower regions

Question 53

what type of muscle lines the upper part of the anus

Answer 53

mucosa and is formed by anal columns and they combine at the pectineal line to form anal values

Question 54

what type of muscle lines the lower part of the anus

Answer 54

nonkeritanised stratified squamous epithelium

Question 55

what is the anocutaneous line

Answer 55

ends the anal pecten and becomes true skin leading to the anal orifice

Question 56

what is the anal sphincter complex

Answer 56

made up of the internal and external anal sphincters

Question 57

what is the structure of the internal sphincter

Answer 57

its a tight spiral either side of the rectum

Question 58

where does the external sphincter attach

Answer 58

posteriorly to the anococcygeal and posteriorly to the perineal body

Question 59

where is the perineum located

Answer 59

inferior to the pelvic floor and between the thighs

Question 60

what are the two triangle kind of parts of the perineum

Answer 60

the urogenital triangle which is anterior and inferior | the anal triangle which is inferior and posterior at 120 degrees to the urogenital triangle

Question 61

what nerve innervates the anal triangle

Answer 61

rectal branch of the pudenal and anterior rami S4

Question 62

describe the structure of the ischioanal fossa

Answer 62

funnel shape on the pelvic floor

Question 63

what muscles/ligaments form the ischioanal fossa

Answer 63

ischium wall, obturator internus and sacrotuberous ligament

Question 64

what structures are attached to the superficial perineal pouch

Answer 64

roots and joining of the erectile structures that form the external genitalia