What Causes Koilonychia?

Koilonychia or spoon nails is a deformity of an individual's nails that causes them to take on the appearance of a concave and spoon-like shape. Koilonychia begins as nails that are flat on the surface and not rounded. This deformity is typically first noticed in an individual's fingernails rather than in their toenails. The nails become increasingly soft, and the indentation that develops in the middle is typically big enough to hold a bead of liquid. Koilonychia is more common in infants where it resolves on its own, but it can be indicative of a serious medical condition when it occurs in adults. The treatment for this nail dystrophy is dependent upon its underlying cause.