Anonychia or anochalia is the inability to develop nails (change in shape, impaired growth). It may be a consequence of various pathological conditions and diseases. It is considered as an independent disease - a hereditary disorder of nail development. Signs and symptoms: deformation of the nail plate, its shortening, thickening, local thickening of the ends of the fingers, splitting of the nail plate, loss of tips, dullness of color and brittleness of the nail, curvature of the fingers. Local phenomena - skin diseases on the fingers, dry areas of skin between the fingers; nail folds: with hypertrophy – thickened, painful on palpation; with atrophy -