Histology, Nail

In most primates, nails are unique features consisting of compact, translucent, keratinized cells. They protect the distal dorsal area of digits and participate in multiple functions, including grip, fine motor movements, and scratching. Like hair, nails are ectodermal appendages whose histology shares similarities and differences with the skin.

Nail abnormalities can result from local nail pathology or manifest underlying systemic disease. A nail biopsy may be warranted to provide a definitive diagnosis, and understanding the macroscopic and microscopic nail histology is an essential aid to the clinicopathological diagnosis of nail diseases.