Left upper quadrant

The human abdomen is divided into regions by anatomists and physicians for purposes of study, diagnosis, and therapy. In the four-region scheme, four quadrants allow localisation of pain and tenderness, scars, lumps, and other items of interest, narrowing in on which organs and tissues may be involved. The quadrants are referred to as the left lower quadrant, left upper quadrant, right upper quadrant and right lower quadrant, as follows below. These terms are not used in comparative anatomy, since most other animals do not stand erect.

Left lower quadrant:

Left upper quadrant:

Right upper quadrant:

Right lower quadrant:

If abdominal pain or signs of peritonitis are localised in the LLQ, colitis, diverticulitis, ureteral colic or pain due to ovarian cysts or pelvic inflammatory disease may be suspected. Examples of tumors in the left lower quadrant include colon cancer and ovarian tumor.

The LUQ may be painful or tender in the case of intestinal malrotation. The RUQ may be painful or tender in hepatitis, cholecystitis, and peptic ulcer. The RLQ may be painful and/or tender in such conditions as appendicitis.

...
Wikipedia