ABDOMINAL ANATOMY

Question 1

simple way of dividing the anterior abdominal wall

Answer 1

four quadrants: right upper, right lower, left upper and left lower

Question 2

more complicated way of dividing the abdominal wall

Answer 2

9 quadrants

two vertical mid clavicular lines

two horizontal lines (trans-pyloric at L1 or subcostal plane L3 or trans tuebcular plane L5)

Right hypochondrium, epigastric, left hypochondrium

right lumbar, umbilical, left lumbar

right iliac/inguinal, pubic/hypogastric, left iliac/inguinal

Question 3

anterior abdominal wall functions

Answer 3

firm yet flexible boundary which keeps the abdominal viscera within the abdominal cavity, maintain their anatomical position

protect abdominal viscera from injury

assists forceful expiration by pushing abdominal viscera upwards

increases intra-abdominal pressure

Question 4

what is the anterior abdominal wall formed of?

Answer 4

skin, superficial fascia, muscles and associated fascia and parietal peritoneum

Question 5

two groups of muscles in the anterior abdominal wall

Answer 5

flat muscles- situated laterally on either side of the abdomen

vertical muscles- situated midline of the body

Question 6

flat muscle structures + function

Answer 6

fibres run in differing directions and cross each other- strengthen the wall and decrease risk of herniations

each muscle forms an anteriomedial aponeurosis

Question 7

what do the aponeuroses form in the midline?

Answer 7

linea alba

Question 8

how many flat muscles?

Answer 8

3

Question 9

what is the inguinal canal?

Answer 9

a canal formed between the deep inguinal ring and the superficial inguinal ring

Question 10

boundaries of inguinal canal

Answer 10

roof- transveralis fascia, internal oblique

posterior wall, transversalis fascia

anterior wall- aponeurosis of external oblique, internal oblique

floor- inguinal ligament

Question 11

inguinal canal function

Answer 11

women- carries round ligament of uterus, ilioinguinal nerve etc

men- spermatic cord and its contents, ilioinguinal nerve

Question 12

consequence of a deficiency in the abdominal wall

Answer 12

inguinal hernias

Question 13

explain inguinal hernias

Answer 13

abdomen is not strong enough

results in protrusion of abdominal cavity contents into the inguinal canal

Question 14

posterior abdomen structure

Answer 14

formed of diaphragm and its crura

psaos major and minor form from diaphragm and insert onto iliac crest

quadratus lumborum forms sides

illiacus originates from iliac crest and becomes the iliopsoas and inserts onto the lesser trochanter of femur

Question 15

what is the pelvic floor?

Answer 15

a muscular partition formed by muscles that separates the pelvic cavity above from the perineal region

Question 16

structure of pelvic floor

Answer 16

right and left levator ani muscles, lying almost horizontally with the pelvis

Question 17

levator ani components

Answer 17

pubococcygeus, puborectaluis and iliococcygeus

coccygeus muscle

associated connective tissue

Question 18

function of pelvic floor

Answer 18

provide support for pelvic viscera e.g bladder, intestines and uterus

help maintain continence as part of the urinary and anal sphincters

Question 19

peritoneum definition

Answer 19

a serous membrane that lines the walls of the abdominopelvic cavity and covers the abdominopelvic organs

Question 20

two groupings of structures within the abdomen + definition

Answer 20

retroperitoneal- organs in contact with the posterior abdominal wall. Not covered with visceral peritoneum, only anterior surface covered with parietal peritoneum

intraperitoneal- further away from the wall, completely invested in peritoneum

Question 21

two types of peritoneum + location

Answer 21

visceral- lining the organs

parietal- lining the cavity

Question 22

what is the peritoneal cavity + what can it be divided into?

Answer 22

space between the two peritoneal membranes, filled with peritoneal fluid

subdivided into the greater sac and the lesser sac

Question 23

two different types of retroperitoneal organs + definition

Answer 23

primarily retroperitoneal- organs developed and remain outside the parietal peritoneum

secondarily retroperitoneal organs- initially intraperitoneal suspended by mesentery. Mesentery fused with posterior abdominal wall

Question 24

examples of primarily retroperitoneal structures

Answer 24

kidneys, oesophagus, rectum

Question 25

examples of secondarily retroperitoneal structures

Answer 25

ascending and descending colon

Question 26

pneumonic to help remember which viscera are retroperitoneal

Answer 26

SAD PUCKER

S- suprarenal glands
A- aorta
D- duodenum (except proximal 2cm)
P- pancreas (except tail)
U- ureters
C- colon (ascending + descending)
K- kidneys
E- esophagus
R- rectum

Question 27

Spleen location

Answer 27

upper left quadrant abdomen- left hypochondrium

Question 28

why can the spleen not be palpated?

Answer 28

under cover of the diaphragm and ribcage

Question 29

anterior anatomical relation

Answer 29

stomach

Question 30

posterior anatomical relation

Answer 30

diaphragm, left lung and ribs 9-11

Question 31

inferior anatomical relation

Answer 31

left colic flexture (splenic flexture)

Question 32

medial anatomical relation

Answer 32

left kidney, tail of pancreas

Question 33

arterial blood supply to spleen

Answer 33

splenic artery, from coeliac trunk

splenic artery then branches into 5 vessels, do not anastamose

Question 34

venous drainage of spleen

Answer 34

splenic vein

combines with superior mesenteric vein to form the hepatic portal vein

Question 35

role of spleen

Answer 35

turnover of red blood cells