Your appendix sits on the lower right side of your abdomen. It’s a small, finger-shaped pouch that sticks out from the cecum, which is the first part of your large intestine, right where the small intestine connects to it. If you drew a line from your belly button to the bony point at the front of your right hip, the appendix sits roughly at the midpoint of that line.
Pinpointing the Exact Spot
Doctors use a landmark called McBurney’s point to locate the appendix during a physical exam. It falls about one-third of the way along an imaginary line drawn from the right hip bone to the belly button, roughly 1.5 to 2 inches from the hip bone. When a doctor presses this spot with one finger and you feel sharp tenderness, it’s one of the strongest indicators of appendicitis. In studies, tenderness at this exact point has a sensitivity of 87% and specificity of 90% for detecting an inflamed appendix.
Why Pain Doesn’t Always Start on the Right
One of the most confusing things about appendicitis is that the pain usually doesn’t begin where the appendix actually is. It typically starts as a vague, mild ache near the belly button. Over the next 12 to 24 hours, the pain migrates to the lower right side, becoming sharper, more constant, and more intense. This shift happens because the inflammation initially irritates nerves deep in the abdomen that the brain reads as central belly pain. Once the swollen appendix presses against the abdominal wall lining, the pain localizes to its true location on the right.
Not everyone follows this textbook pattern. Up to 65% of people have a “retrocecal” appendix, meaning it curls behind the cecum instead of hanging down from it. This position can cause pain in the right flank or even the back rather than the classic lower right spot. Retrocecal appendicitis is often diagnosed later, sometimes not until the appendix has already ruptured, because the pain doesn’t match what patients or doctors expect.
Can the Appendix Be on the Left Side?
In extremely rare cases, yes. A condition called situs inversus totalis mirrors all the internal organs, placing the appendix on the lower left side instead. This affects somewhere between 1 in 10,000 and 1 in 100,000 people. Left-sided appendicitis can also occur with a developmental variation called midgut malrotation, where the intestines didn’t rotate into their usual position during fetal development. Most people with these conditions don’t know about them until imaging reveals the unusual layout.
What Else Causes Right Lower Abdominal Pain
Because several organs and structures overlap in the lower right abdomen, pain in that area doesn’t automatically mean appendicitis. Kidney stones or a urinary tract blockage on the right side can produce similar sharp pain. Crohn’s disease commonly inflames the end of the small intestine, which sits in the same neighborhood as the appendix. In women, a ruptured or bleeding ovarian cyst and pelvic inflammatory disease are frequent mimics. Right-sided diverticulitis, swollen lymph nodes in the abdomen (mesenteric adenitis), and infections of the lower intestine can all produce tenderness in the same spot.
How Appendicitis Is Confirmed
A physical exam checking for tenderness at McBurney’s point is the first step, but imaging usually follows to confirm the diagnosis. CT scans are the gold standard, with a sensitivity of about 97% and specificity of 96%. When contrast dye is used both orally and intravenously, accuracy climbs even higher, catching over 99% of cases. Ultrasound is less precise overall, with sensitivity around 82% and specificity near 86%, but it’s the preferred first choice for children and pregnant women because it avoids radiation exposure. Low-dose CT scans offer a middle ground, maintaining strong accuracy (about 93% sensitivity) while cutting radiation significantly.
If you’re experiencing pain that started near your belly button and has shifted to the lower right over several hours, especially with nausea, fever, or pain that worsens when you move or cough, that pattern is the hallmark of appendicitis and warrants prompt evaluation.