Fingernail

Fingernails are hard, keratin-rich plates that cover the dorsal tips of the fingers. They form a protective shield for the sensitive fingertip, aid in manipulating small objects, and help enhance fine touch and precision.

Anatomy and structure include several components. The visible nail plate rests on the nail bed, which supplies nourishment. The proximal nail fold overlaps the plate and forms the cuticle (eponychium). The hyponychium lies beneath the free edge of the nail. The lunula is a pale, crescent-shaped area at the base of the nail, signaling the visible part of the underlying nail matrix, which generates new nail cells that are pushed outward as the nail grows.

Growth and development: Fingernails grow from the matrix located under the proximal nail fold. Nail growth rates vary but are typically about 3 millimeters per month for fingernails, with slower growth in older individuals. Growth can be influenced by age, health, nutrition, and environmental factors; illness or malnutrition can slow growth or alter appearance.

Function and care: Regular trimming, gentle filing, and moisturization help maintain nail health. Avoiding bites, excessive moisture, and harsh chemicals reduces damage. The nails can reflect overall health; changes in color, thickness, or shape may indicate underlying conditions that warrant medical evaluation.

Common issues include fungal infections (onychomycosis), paronychia around the nail folds, ridges or pitting associated with systemic disease or psoriasis, and ingrown nails when the edge grows into the skin. Proper nail hygiene supports function and reduces risk of complications.