The clinical signs of lichen planus of the nails are reviewed. The inflammatory process of lichen planus may involve any or all of the four nail components; however, it may result in scarring of only the matrix with consequent obliteration of the correspondingly produced portions of the nail plate. Depending on the size of the lesion, intensity of inflammation, and scar produced, the nail plate changes may be permanent or temporary.
Characteristically, one sees: (1) irregular, longitudinal grooving and ridging of the nail plate; (2) "pterygium" formation; (3) shedding of the nail plate with atrophy of the nail bed; (4) subungual keratosis; and (5) subungual hypergimentation.
Because of the destructive nature of lichen planus in the nail, the importance of early nail biopsy in the diagnosis of this disease is stressed. Treatment with systemic prednisone may prevent complete nail atrophy.
Zaias N. The Nail in Lichen Planus. Arch Dermatol. 1970;101(3):264-271. doi:10.1001/archderm.1970.04000030008002