Nail biology, morphologic changes, and clinical ramifications: part I.

The nail, a well-recognized and fascinating appendage of the skin, represents an invaluable clinical means to facilitate the diagnosis of a number of dermatoses; hence, the authors considered it worthwhile to examine the physiopathologic alterations affecting the nail morphology, including shape, attachment, surface, and color. The accurate definitions of nail abnormalities in various cutaneous disorders have been delineated and their clinical ramifications have been recounted.