Lecture 2; Anterior abdominal wall and peritoneum

Question 1

Answer 1

Question 2

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

Question 7

Answer 7

Question 8

Answer 8

Question 9

Answer 9

Question 10

Answer 10

Question 11

Answer 11

Question 12

Answer 12

Question 13

What are the boundaries of the abdominal cavity?

Answer 13

Superior; Diaphragm, inf. thoracic aperature

Inf; Iliac crest, inguanal ligament, pelvic inlet

Post; Poas major, quadratus lamborum

Ant and lat; abdo wall muscles

Question 14

What is the fibre orientation of the External and Internal Obliques & Transversus abdominus?

Answer 14

External Oblique; Inferior medially (hands in pockets)

Internal Oblique; Supero-medially

Transversus abdominus; Transverse

Question 15

Whats the rectus sheath?

Answer 15

Acruate line that is roughly halfway along line from umbilicus to pubic bones

Question 16

What is the arterial supply of the abdominal muscles?

Answer 16

Superior epigastric (from internal thoracic)

Inferior epigastric (from external iliac)

Both artiers run underneath rectus abdominus (On top of transversalis fascia and within the rectus sheath) and anastamose together.

Question 17

What other arteries supply the abdominal muscles?

Answer 17

Deep circumflex iliac

Musculophrenic branches

Intercostal

Lumbar

Iliolumbar

Question 18

What nerves supply the abdominal wall?

Answer 18

T7-12 lateral and anterior cutaneous nerves

Iliohypogastric / Ilioguinal (L1) nerves

Travels in neurovascular plain between internal oblique and trasversus abdominus

Question 19

What is the sensation of the peritoneum?

Answer 19

Parietal; Sensitive to pain, touch, temperature and pressure (Somatic, phrenic and obturator nerves)

Visceral/Mesenteries; Sensitive to stretch, chemical insult etc. (ANS) i.e stretch if you eat too much

Question 20

What organs are suspended by mesentaries?

Answer 20

Midgut and hindgut = dorsal mesentary

Foregut = Dorsal and ventral mesentary (Embryological development)

Whole of GI suspended

Question 21

Which organs are suspended by mesentaries, name the mesentary too;

Answer 21

Jejenum + Ilium = The mesentary

Transverse colon = transverse mesocolon

Sigmoid colon = sigmoid mesocolon

BUT retroperitoneal / no mesentary

• distal duodenum
• ascending and descending colon
• Part of rectum

Question 22

Which organs are retro-peritoneal?

Answer 22

Kidneys, pancreas, distal duodenum, ascending and descending colon, and upper 2/3 rectum

Question 23

What is the greater sac?

Question 24

What is the lesser sac?

Answer 24

Behind lesser omentum and stomach (Created due to rotation of theforegut structures, drags lesser omentum around to create pocket)

Question 25

What is the omental foramen and what creates it?

Answer 25

Ant.; Free edge of lesser omentum (portal triad) Post; IVC Hepatoduodenal and heaptogastric ligaments forms roof.

Question 26

What are the paracolic gutters?

Answer 26

Paracoli sulci lateral to asc. and desc. colon. Left side limited by ligament thus RHS more important as continuous with omental bursae

Question 27

Describe the fluid migration of the peritoneum;

Answer 27

If sitting fluid moves down and presents as acute apendicitis If supine, fluid migrates into lesser sac or pouch or morrison and sits there