Pectus carinatum is a condition in which the sternum (breastbone) protrudes, or sticks out, more than usual. It is the opposite of pectus excavatum, in which the breastbone is depressed inward and gives the chest a sunken appearance.

What causes the sternum to protrude?

Other names are chest protrusion, protruding chest or protruding sternum. The condition may be caused by excessive growth of cartilage. Pectus carinatum can be present at birth, although it can also occur during adolescence, emerging suddenly during the growth spurt at puberty.

Why does my upper chest stick out?

Pectus carinatum is a genetic disorder of the chest wall. It makes the chest jut out. This happens because of an unusual growth of rib and breastbone (sternum) cartilage . The bulging gives the chest a birdlike appearance.