What nail condition is described as a spoon-shaped nail?

The condition referred to as a spoon-shaped nail is koilonychia. This nail condition is characterized by a concave or spoon-like shape of the nail plate, which can often appear thin and brittle. Koilonychia is typically associated with various systemic conditions, including iron deficiency anemia, where the lack of iron can affect the nail's structure.

In contrast, pterygium involves the abnormal attachment of the skin to the nail plate, leading to the potential disruption of nail growth. Onychoptosis refers to the shedding or falling off of nails, while onychatrophia denotes the wasting away or atrophy of the nail. Each of these conditions has distinct characteristics that do not match the spoon-shaped appearance of koilonychia. Therefore, understanding the unique traits of each condition allows for accurate identification, with koilonychia standing out due to its specific cosmetic and clinical presentation.