A seminar presentation on gross anatomy of the large intestine

1. NAME: Ebere Uchenna Emmanuel
REG. NO.: 2017/MD/6106
DEPT.: Anatomy
COURSE CODE: ANA 441
SUPERVISOR: Dr. Ezemagu
GROSS ANATOMY OF
THE COLON
A Seminar presentation by:

2. OUTLINE
01
02
03
04
05
OVERVIEW OF THE LARGE
INTESTINE
DIVISIONS OF THE LARGE
INTESTINE
GENERAL FEATURES OF THE COLON
THE CAECUM
THE VERMIFORM APPENDIX
06 THE ASCENDING COLON
07
08
09
10
11
TRANSVERSE COLON
DESCENDING COLON
SIGMOID COLON
VASCULAR SUPPLY
NERVE AND LYMPHATICS
12 CLINICAL ANATOMY

3. − The large intestine measures 1.5m in
the adult.
− Extends from the ileoceacal junction with
the appendix vermiformis (in the right
iliac fossa) to the anus.
Functions
− Absorbs fluid from the indigestible
chyme
− Converts the chyme to semi-solid stool
− Temporarily store and allow to
accumulate until defecation occurs.
01| OVERVIEW OF THE LARGE INTESTINE

4. 02| DIVISIONS OF THE LARGE INTESTINE
• Caecum (6cm)
• Appendix vermiformis (9cm)
• Ascending colon (15cm)
• Transverse colon (50cm)
• Descending colon (25cm)
• Sigmoid colon (50cm)
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5. 1. Appendices epiploicae: Fat-filled
peritoneal processes present over
the surface of caecum, AC, TC, DC,
and the SC.
2. Taenia coli: These are three distinct
longitudinal bands: mesocolic
omental tenia, and libera taenia.
3. Haustra: Sacculations of the wall of
the colon between the taenia.
03| GENERAL FEATURES OF THE COLON
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6. 04| THE CAECUM
The caecum, is the first part of the large
intestine and it is a blind pouch.
− Lies in the right iliac fossa,
− Between caecum and ileum is the ileocecal
valve - prevents reflux during peristalsis.
− May be palpable through the ant. lat. abd.
wall if distended with feces.
− Continuous with the AC.
− The vermiform appendix is attached.
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7. 05| THE VERMIFORM APPENDIX
The appendix vermiformis, (L. wormlike)
is a blind intestinal diverticulum
attached at the posteromedial aspect of
the caecum.
− Contains large amount of lymphoid
tissue - has no vital function.
− Variable position
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8. 06| THE ASCENDING COLON
The ascending colon, is the second part
of large intestine.
− Passes superiorly on the right side of
the abdominal cavity from the caecum
to the right lobe of the liver
− It forms the right colic flexure at the
right lobe of the liver.
− It is retroperitoneal.
ANATOMICAL RELATIONS:
− ANTERIOLY:
− Small intestine,
− Greater omentum,
− Ant. Abd. Wall
− POSTERIORLY:
− Iliacus,
− Right kidney,
− Quadratus lumborum
− ANTERO-MEDIALLY:
− Fundus of gallbladder

9. 07| THE TRANSVERSE COLON
The transverse colon, is the third part of
large intestine.
− Extends from the right colic flexure to
the spleen.
− From the spleen, it turns 90o degrees to
point inferiorly forming the left colic
flexure.
− The TC is the least fixed and has a
variable position (can dip into the pelvis
in tall, thin individuals)
− The TC is the only part which is
intraperitoneal.
ANATOMICAL RELATIONS:
− ANTERIOLY:
− Greater omentum,
− Ant. Abd. Wall
− POSTERIORLY:
− Duodenum,
− Head of pancreas
− Spleen

10. 08| THE DESCENDING COLON
The descending colon, is the fourth part of
large intestine.
− After the left colic flexure, the colon moves
down towards the pelvis – forms the DC.
− It is retroperitoneal.
ANATOMICAL RELATIONS:
− ANTERIOLY:
− Small intestine,
− Greater omentum,
− Ant. Abd. Wall
− POSTERIORLY:
− Iliacus,
− Quadratus lumborum,
− Left kidney

11. 09| THE SIGMOID COLON
The sigmoid colon, is the fifth part of large
intestine.
− When the DC turns medially, it
becomes the SC.
− Located in the left lower quadrant.
− Extends from left iliac fossa to S3.
ANATOMICAL RELATIONS:
− SUPERIORLY:
− Bladder,
− Uterus
− INFERIORLY:
− Anus

12. 10|VASCULAR SUPPLY
©
2014
WebMD,
LLC.
All
rights
reserved

13. 11| NERVE AND LYMPHATICS
INNERVATION
− Sympathetic and parasympathetic nerves:
From superior mesenteric plexus.
LYMHATICS
− Ascending and transverse colon: Drains
into the superior mesenteric nodes.
− Descending and sigmoid colon: Drains into
the inferior mesenteric nodes.

14. 12| CLINICAL ANATOMY
• Colitis: Inflammation of the colon.
• Caecal volvulus: Twisting of the caecum –
represents 10% of intestinal volvuluses.
• Colon cancer: Cancer of colon affects more than
100,000 people each year, though it is usually
preventable through regular screening that is
colon biopsies.
• Appendicitis: Inflammation of the appendix.
• Appendectomy: Surgical removal of the inflamed
appendix.
• Marginal Artery of
Drummond: The marginal
artery of Drummond is a
clinically important vessel that
provides collateral supply to
the colon – thereby
maintaining arterial supply in
the case of occlusion or
stenosis of one of the major
vessels.
© 2014 WebMD, LLC. All rights reserved

15. 13| REFERNCES
• Susan Standring (2015). Gray's Anatomy - The Anatomical Basis of Clinical Practic
e 41st Edition. MSCambo Elsevier
• Singh I. Blood Vessels of Stomach, Intestines, Liver, Pancreas and Spleen. In: Textb
ook of Human Anatomy (Textbook of Anatomy), 5th ed. Jaypee Brothers Medical
Publishers(P)Ltd. New Delhi; 2015.p. 583-585.
• BD Chaurasia’s Human Anatomy, Volume 2 – Lower Limb, Abdomen and Pelvis,
6th Edition. P
.278-295
• Moore K.L., Arthur F.D., Anne M.R.A. Bones of Upper limb. Clinically Oriented An
atomy, 8th ed. Lippincott Williams and Wilkins Publishers.Philadelphia;2018. p.153-
154.
• Netter F., Machado C., Hassen J. Atlas of Human Anatomy,7th ed. Elsevier: Saund
ers.Philadelphia;2014. p.416.
• https://teachmeanatomy.info/abdomen/gi-tract/cecum
• https://teachmeanatomy.info/abdomen/gi-tract/appendix
• https://en.m.wikipedia.org/wiki/colon

16. THANKS FOR LISTENING