A bifid rib or bifurcated rib or sternum bifidum is a congenital abnormality occurring in about 1.2% of the population. Bifid ribs occur in up to 8.4% of Samoans. The sternal end of the rib is cleaved into two. It is usually unilateral.
Effects of this neuroskeletal anomaly can include respiratory difficulties, neurological difficulties, limitations,and limited energy from the stress of needing to compensate for the neurophysiological difficulties, but bifid ribs are usually asymptomatic. They are often incidentally discovered by chest x-ray.