Nail deformities may present as either medical or cosmetic problems, often requiring surgical intervention. These deformities have a number of etiologic factors including infections, inflammatory disease processes, congenital abnormalities, trauma, tumors, and systemic diseases. Nails function to protect the distal phalanges and finger tips from injury, enhance fine touch and digital movement, assist in scratching and grooming, and serve as an aesthetic and cosmetic adornment.

The term “nail unit” is used to describe the nail and its surrounding structural components. A thorough understanding of the structural and functional organization of the nail unit is necessary for correct diagnosis and treatment of nail diseases and deformities.