Pelvic Colon

Question 1

Site

Answer 1

1. Begins: in left iliac fossa at pelvic brim as continuation of descending colon
2. Ends: in pelvic cavity opposite 3rd sacral piece by becoming continuous with rectum

Question 2

Shape

Answer 2

S-shaped

Question 3

Length

Answer 3

15-20 inches long

Question 4

Peritoneal covering

Answer 4

Completely covered by peritoneum and has triangular shaped mesentery (pelvic or sigmoid mesocolon)

Question 5

Pelvic mesocolon

Answer 5

Peritoneal fold formed of 2 layers attaching pelvic colon to upper part of pelvis posterior wall

Question 6

Borders

Answer 6

1. Free border
2. Attached border (root): 2 limbs (lateral and medial)

Question 7

Free border

Answer 7

Contains sigmoid colon

Question 8

Lateral limb

Answer 8

1. Attached to lateral external iliac vessels medial side alone line starting 2 inches above Inguinal ligament
2. Ascend upwards to bifurcation point of left common iliac artery

Question 9

Medial limb

Answer 9

1. Descends from apex till 3rd sacral piece being attached to front of sacrum
2. Apex crosses in front of left ureter at left common iliac artery bifurcation

Question 10

Intersigmoid recess site

Answer 10

1. Lies deep to pelvic mesocolon apex
2. Its opening downwards

Question 11

Contents

Answer 11

1. Sigmoid colon in free border
2. Sigmoid vessels in lateral limb
3. Superior rectal vessels in medial
4. Lymph vessels and nodes
5. Autonomic fibers
6. Extraperitoneal fat

Question 12

Relations: below

Answer 12

1. Urinary bladder in both sexes
2. Uterus in female

Question 13

Relations: posterior

Answer 13

1. Left piriformis
2. Sacral plexus
3. Left ureter
4. Left internal iliac vessels

Question 14

Relations: above and medial

Answer 14

Ileum coils

Question 15

Relations: lateral

Answer 15

Pelvis lateral wall separated from sigmoid colon by the following:
1. Left external iliac vessels
2. Obturator nerve and vessels
3. Left ovary (in female) or left vascular deferens (in males)

Question 16

Arterial supply

Answer 16

Sigmoid branches of left colic artery

Question 17

Venous drainage

Answer 17

Sigmoid veins into inferior mesenteric vein (portal circulation)