Anatomy of Colon

Question 1

Surface anatomy of Colon

Answer 1

Right grain, right flank, right hypochondriam
Epigastric region
Left hypochandrium, left flank, left groin

Question 2

Surface anatomy of appendix

Answer 2

Right iliac fossa

Question 3

McBurney’s point

Answer 3

One third from ASIS, two thirds from umbilicals third above and two thirds below the line.

Question 4

How is ileum attached to cecum

Answer 4

Lliocecum value

Question 5

Boundaries of assending colon

Answer 5

From cecum to right flexure,related to right kidney superiorly

Question 6

Boundaries of tranverser colon

Answer 6

Attached to Posterior wall-transverse mesocolon
Highly mobile may sag up to umbilicus
greater momentum hangs from free margin- like apron
Starts from right colic fexure to left colic flexure

Question 7

Descending colon

Answer 7

Runs through left lumbar area
Fixed
Lower area- sigmoid colon
Retroperitoneal

Question 8

Sigmoid colon

Answer 8

Attached to posterior wall through sigmoid mesocolon- v-shaped type of mesentry is hihighly mobile can rotate around its own axis causing
Sigmoid voluilus

Question 9

Mesentery of transverse colon discussed

Answer 9

Broad meso-fold of peritoneum connects (TVC) posterior wall
Continuous with to posterior layers of greater momentum
Which inturn after separatingto surround (TVC)join behind it to continue to vertebral column behind it they then diverge infront of anterior border of pancrease providing vessels supplying the (TVC)

Question 10

What derivative is the (TVC) (mesocolon)

Answer 10

Dor sum mesentry in embryo

Question 11

Sigmoid mesocolon

Answer 11

Is the fold of pentoneum containing sigmoid colon is connection with the pelvic wall. It’s line of attachment forms a v shaped where the apex points at common left iliac artery ends at level of, third sacrum medially
Sigmoid and superior rectal vessels runs between fold and runs posterior to uterus which is very important to remember when removing kidney stones

Question 12

Mesoappendix

Answer 12

Is a portion of messentry connecting the ileum to the appendix it may extend to the tip of the appendix and it encloses the appendicular a and v. As well as lymphatic and lymph node

Question 13

What is the autonomic nerve supply of colon

Answer 13

Mid-gut: assending and proximal 2/3 of (TVC)= SMP
Hind-gut: distal 1/3 of (TVC) and descending, sigmoid Colon= IMP (include sensory)
Sympathetic innevation via the pelvic splanchnic nerve with parasympathetic
Via lumber splanchnic nerves.

Question 14

What are the differences of colon and small bowel

Answer 14

1. Teniae coli = no
2. Haustra= no
3. Omentum appendices/ appendices epiploica=no
4. Semicircular folds= circular folds
5. Large diameter = small diameter

Question 15

Anatomy of appendix

Answer 15

Pain
position: follow the tenia coli
Pre- and postileal, sub, retro or paracacecal,
Subhepatic
Retrocolic
Pelvic

Question 16

Paracolic gutters

Answer 16

Right and left paracolic gutter (right= fluid move up and down, left = only down)
Right and left infracolic gutter (right no movement, left only down)

Question 17

What is a subphrenic abscess from appendicitis

Answer 17

A complication of appendicitis (fluid), the # infection has now spread, to the supracolic compartment and subphrenic space

Question 18

Fossa related to ceacum

Answer 18

Superior ileocecal recess= fold of peritoneum arching over the branch of ileocolic artery which supplies ileocolic junction (fossa is narrow situated between small intestine-ileum-caecum
Inferior ileocecal recess= situated behind the angle of the junction of the caecum formed by ileocecal fold of peritoneam upper border fixed to the ileum lowe border passes ileocecal junction to veriform process or appendix
Retrocaecal recess= bounded on the right by ceacal fold

Question 19

Blood supply of midgut

Answer 19

Inferior pancreaticoduodenal artery, intestinal arteries,vascular arcades, straight arteries, middle colic artery, right colic artery, marginal arteries, lleocolio artery

Question 20

Hind gut blood supply

Answer 20

Left colic artery, marginal artery of Drummond, signaled branches, superior rectal artery, rectosigmoid

Question 21

Anastomoses of mid and hind gut

Answer 21

Occur at the marginal artery of Drummond

Question 22

Formation of portal system

Answer 22

SMV as well as splenic vein that join to form portal vein

The IMV drain into splenic vein

Question 23

Portal-caval anastomoses

Answer 23

1. Oesophagus (left gastric vein-azygos vein)
2. Rectum (superior rectal vein-middle and inferior rectal veins and pelvic venous plexus)
3. Umbilicus (para-umbilical veins - superficial and inferior epigastric veins)
4. Bare areas of retro peritoneal organs (visceral veins, colic, splenic and portal veins-retroperitoneal veins of the post abdominal wall)

Question 24

Explain lymphatic drainage of cecum and appendix

Answer 24

Drain into ileocolic lymph nodes

Question 25

Lymphatic drainage of ascending colon and transverse

Answer 25

• Epicolic lymph nodes
• para colic = 1. ileocolic nodes, 2. Right colic and middle colic nodes
• eventually in Superior mesenteric lymph nodes

Question 26

Lymph drainage of distal 1/3 of transverse colon and descending and sigmoid

Answer 26

• Epicolic lymph nodes
• Paracolic lymph nodes = left colic nodes
• eventually in interim mesenterio lymph nodes
  (However left colic flexure → Superior mesenteric nodes)

Question 27

What is the blood supply of rectum

Answer 27

1. Proximal part= Superior rectal artery
2. Middle and inferior parts = middle rectal arteries
3. Internal pudendal = inferior rectal arteries
4. Anorectic junction and anal canal _ median sacral arteries as well as inferior rectal arteries

Question 28

Lymph drainage of rectum

Answer 28

Pararectal nodes and sacral nodes

Question 29

What and the innovation of sphincter

Answer 29

IAS = autonomic
EAS= inferior rectal nerve