Tags: Disease.
A bifid rib (bifurcated rib or sternum bifidum) is a congenital abnormality of the rib cage and associated muscles and nerves which occurs in about 1.2% of humans. Bifid ribs occur in up to 8.4% of Samoans. The sternal end of the rib is cleaved into two. It is usually unilateral. Bifid ribs are usually asymptomatic and are often discovered incidentally by chest X-ray.