What are the anatomical regions and quadrants of the abdomen?

The abdomen can be divided into nine anatomical regions and four quadrants. These classifications are useful to clinicians during an abdominal exam because they can help with differential diagnoses and communication between healthcare providers.

From superior to inferior, the abdomen is divided into nine regions:

1. Epigastric
2. Umbilical
3. Hypogastric (e.g., suprapubic)
4. Left hypochondriac
5. Right hypochondriac
6. Left lumbar
7. Right lumbar
8. Left iliac (e.g., inguinal)
9. Right iliac (e.g., inguinal)

Midline anatomical regions: epigastric, umbilical, and hypogastric

There are three anatomical regions in the midline of the abdomen. These include the epigastric, umbilical, and hypogastric (e.g., suprapubic) regions.

Bilateral anatomical regions: hypochondriac, lumbar, and iliac

Each bilateral anatomical region has an associated right and left side. Adjacent to the epigastric region are the right and left hypochondriac regions; adjacent to the umbilical region are the right and left lumbar regions. On either side of the hypogastric region are the right and left iliac regions, which can also be referred to as the right and left inguinal regions.

The abdomen can also be divided into four quadrants, known as the right upper, the left upper, the right lower, and the left lower quadrants. It is common to see these quadrants abbreviated as RUQ, LUQ, RLQ, and LLQ, respectively.

The four quadrants of the abdominal wall are used for general clinical descriptions. The quadrants are defined by the transumbilical and medial planes. The transumbilical (or horizontal) plane passes through the umbilicus at the L4 level, and the vertical medial plane divides the body into the right and left halves.

It is important to know the anatomical regions (and quadrants) of the abdomen to correlate the pain to the organs contained in each area. For example, pain within the epigastric region should guide you to think about the stomach, liver, pancreas, duodenum, and adrenal glands. Pain in the suprapubic (e.g., hypogastric) region should guide you to think about the bladder, sigmoid colon, rectum, and uterus.

Organization of the abdomen in this manner allows for universal communication among healthcare providers and aids in differential diagnoses.

That’s it for now. If you want to improve your understanding of key concepts in medicine, and improve your clinical skills, make sure to register for a free trial account, which will give you access to free videos and downloads. We’ll help you make the right decisions for yourself and your patients.