Koilonychia

Koilonychia is a condition that affects the toenails, characterized by thin, spoon-shaped nails. In this condition, the nails become excessively concave or spoon-shaped, with raised outer edges and a thin, brittle texture.

This can result in a more flattened or depressed appearance of the nails. Koilonychia can be caused by a variety of factors, including genetic predisposition, iron deficiency anemia, trauma to the nails, or certain underlying medical conditions.