Pincer nails

Pincer nails (also known as "Omega nails," and "Trumpet nails") are a toenail disorder in which the lateral edges of the nail slowly approach one another, compressing the nailbed and underlying dermis. It occurs less often in the fingernails, and there usually are no symptoms. .

Hereditary pincer nails have been described although the genes or mutations causing the hereditary form seem to be unknown.