Appendix Location: Typical & Atypical anatomy (Doctor Explains).

Appendix location in your body?

A. Typical appendix location.

The appendix is a small, finger-like, blind-ended tubular structure that arises from the first part of your colon (called the caecum).

The appendix location is typically in the right iliac fossa (the lowermost right quadrant of your abdomen near the right hip bone. It is considered a part of your large intestine.

Here are some anatomical facts about the appendix:

• Length: 3.5 Inch (9 cm); it can range from 2-13.8 inches.
• Diameter: 0.24 inch (0.6 cm). a diameter of more than 6 cm is considered (inflamed appendix).
• The appendix’s base is 2 cm beneath the ileocaecal valve (the junction between the small and large intestines).
• The Tip of the appendix is variable in location; symptoms of appendicitis (appendix pain) are determined by the appendix’s tip location.

B. Variations in appendix tip location.

The appendix tip (the blunt end) is not attached to other abdominal organs. So, its location may vary relative to the nearby caecum (first part of the colon).

The table below illustrates the variation in the appendix tip (reference). These variations are important because they may influence the symptoms (pain character and location) when the appendix inflames.

C. Atypical Appendix locations.

In rare cases, the appendix may present in atypical locations, such as (reference):

• Left lower abdomen (left iliac fossa): it is considered a congenital anomaly (mal-rotated intestine) or in patients with a rare condition called (Situs Inversus Totalis).
• Next to the Duodenum.
• In the scrotum (as a part of inguinal hernia).
• Right gluteal region.
• Lateral abdominal pouch.
• Retro-renal (behind the right kidney).
• Retro-psoas (behind the psoas muscle).

How different appendix locations are related to symptoms.

The symptoms of acute appendicitis (appendix pain location, severity, and character) may vary according to the site of the appendix and its tip.

So, the appendix locations described above are important to understand. Here are how these appendix locations may influence the symptoms.

• Retrocecal appendix (most common form) may cause dull, poorly localized pain that is often not as sharp as the anteriorly-located appendix. Also, the retrocecal appendix cause right lower pain on hip extension (psoas sign) which is often absent in other types.
• The pelvic appendix may cause atypical symptoms such as diarrhea, tenesmus, constipation, frequent urination, or dysuria. Also, the site of tenderness in the pelvic appendix is usually lower (below McBurney’s point).
• The left-sided appendix may cause lower left quadrant pain.

How does a doctor examine appendix location?

Your doctor defines the appendix’s location to examine it. He defines a specific point at which pain is at its maximum (called McBurney’s point).

When McBurney’s point is pressed, severe pain and tenderness arise. This point typically correlates with the appendix base location.

McBurney’s point lies one-third of the distance between the right ASIS (anterior superior iliac spine) and the umbilicus.

The ASIS is a sharp notch on the upper part anterior border of the right hip bone.

Your doctor elicits appendix pain by pressing on McBurney’s point.

Appendix location in males and females: is there a difference?

There is no difference between men and women regarding the appendix location. The appendix lies in the lower right abdominal quadrant in both males and females.

Female appendix pain location in the lower right quadrant may be confused with right-sided pelvic organ disease, such as left ovarian pain, left fallopian tube pain, and left ectopic pregnancy.

Other causes of pain in appendix location (mimics of appendix pain).

Many diseases and conditions may lead to pain in the appendix location. Differentiation can be impossible in some cases.

Common mimics of appendix pain include:

A. Mimics in both males and females:

• Cecal diverticulitis: a diverticulum is a sac-like pouch that often affects the colon. Cecal diverticulitis occurs when a cecal diverticulum becomes inflamed, infected, or perforated, leading to symptoms mimicking appendicitis.
• Meckel’s diverticulitis: a congenital remnant of the small intestine
• Acute ileitis: acute inflammation of the ileum (the terminal part of your small intestine that opens into the cecum.
• Crohn’s disease: it commonly affects the ileum giving a picture similar to acute appendicitis.
• Right ureteric colic.

B. Female-only Mimics:

• Right tubulo-ovarian abscess.
• Pelvic inflammatory disease.
• Ruptured Right ovarian cyst.
• Mid-cycle ovulation pain (Mittelschmerz).
• Ovarian or fallopian tube torsion.
• Right pelvic endometriosis.

C. Male-only mimics:

• Right epididymitis (inflammation of the epididymis, a coiled tube at the back of testicles).
• Right testicular pain (as with testicular portion).
• Torsion of the appendix testis or appendix epididymis.