Appendix is blind tubular structure present at the ileocecal junction of the gut.


• Appendix develops as an outgrowth from of the cecum in embryonic life at around week 8. It is variable in length and its length varies between 2 and 20 cm and may become inflamed and enlarged owing to faecal impaction and/or infection (appendicitis). • Small mesentery of the Appendix which is triangular in shape called mesoappendix and contains appendiceal blood vessels and lymphatics. HISTOLOGY • Histologically Appendix have these tissue layers, from inside to outside, which include mucosa, lamina propria, inner circular and outer longitudinal smooth muscle, and adventitia. • Mucosa of the Appendix contains numerous goblet cells, intestinal glands, and crypts of Lieberkühn. • Taeniae coli which is longitudinal muscle bands of the large gut which are three in number, merge into a single, outer longitudinal muscle layer on the appendix. • Lamina propria contains masses of lymphoid tissue with germinal centres.

Locations of Appendix

Typical locations of Appendix are

1.retrocecal-retrocolic – it is the most common location and found in about 70-80% cases.

2.pelvic – it is 2nd most common position and seen in 20-25% cases

3. subcecal,

4. ileocecal (anterior to ileum),

5. ileocecal (posterior to the cecum)

Locations of Appendix are variable from person to person and depend on the size of mesoappendix In case of pregnancy it may get pushed down by growing uterus into the pelvis.

Mesentery and Folds


Mesoappendix is the mesentery of Appendix which runs from the posterior leaf of the mesentery of the terminal ileum and posterior to the terminal ileum.

It often remains attached to the lateral side of the cecum in its entire length. It is triangular in shape.

It contains appendicular artery which is a branch of the ileocolic artery.

Ileocolic or Superior Ileocecal Fold

It contains anterior cecal artery and it forms the anterior wall of ileocolic or superior ileocecal fossa.

Ileocecal or Inferior Ileocecal Fold

It lies anterior to mesoappendix and extends from the anterior terminal ileum. It forms the anterior wall of ileocecal or inferior ileocecal fossa. The posterior wall of ileocecal or inferior ileocecal fossa contains no vessels, so it is known as “bloodless” fold of Treves

Vascular Supply

Arterial Supply

Appendicular (Appendiceal) Artery is the main blood supply of the Appendix. It is an end artery. It is a branch of the ileocolic artery in most of the cases. But some anatomical variations can be seen and it may arise from the ileal or colic branch of the ileocolic artery. Ileocolic artery is the branches of the superior mesenteric artery.

Venous Supply

Appendicular vein drains into the ileocolic vein.

Lymphatic Supply

Appendicular lymphatics drain into the superior mesenteric lymph nodes.


stomach, health, diet

Appendicitis is the most common abdominal surgical condition. It is commonly seen in adolescents and young adults in the age group of the 20s with slightly more male cases with respect to the female 1.3:1. It is very rare in infants but when occurs generally has a very severe course. The lifetime risk for appendicitis in the population varies from 10 to 20%.


Most Common cause of appendicitis in adults is faecoilith obstructing the lumen of the Appendix. But in children, it is most commonly due to hyperplasia of lymphoid tissue.


Either due to faecolith or lymphoid hyperplasia, there is lumina obstruction of Appendix, which leads to inflammation, oedema and bacterial infection. When oedema occurs sufficient enough it cut off appendicular vascular supply which increases chances of necrosis and perforation.


Classic Presentation Anorexia, periumbilical pain, vomiting and shifting of pain to right lower quadrant of the abdomen.

Signs present in appendicitis

● Pointing sign-when asked patient point his finger to where the pain began and where it moved

● Rovsing’s sign- Deep palpation of the left iliac fossa causes pain in the right iliac fossa it is known as Rovsing’s sign

● Psoas sign-the patient lie with the right hip flexed for pain relief is the psoas sign.

● Obturator sign- when the hip of patient is flexed and internally rotated it causes pain in the hypogastrium this is known as the obturator test.

Differential Diagnosis

Differential diagnosis of appendicitis
in Adults includes
o Ureteric stone disease
o Peptic ulcer disease
o Diverticulitis
o Pelvic inflammatory disease
o Pyelonephritis
o Ectopic pregnancy
o Torsion/rupture of ovarian cyst
o Intestinal obstruction
o Colonic carcinoma
o Torsion of testis
o Pancreatitis
In children includes
• Gastroenteritis
• Mesenteric adenitis
• Meckel’s diverticulitis

Appendicitis during Pregnancy

Appendicitis is the most common cause of first-trimester acute abdominal pain.

Appendicitis has more incidence in the second trimester, but it is not the commonest cause of acute abdominal pain in 2nd trimester.

Appendicitis has more chances to perforate in the third trimester. In the third trimester usually, there is right upper quadrant pain instead of right lower quadrant pain.

In cases of Appendicular perforation death of Fetus can occur in 35% cases because of delay in diagnosis. As the pain simulates labour pain.


Treatment is bowel rest and intravenous antibiotics in uncomplicated appendicitis.

In complicated cases or those uncomplicated cases Appendicectomy


disclaimer: information provided here is purely for the knowledge purpose and it should not be used as a substitute for medical advice.

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