This condition is a pruritic eruption of unknown etiology. It is not uncommon in childhood. This illustration shows representative lesions of lichen planus on a most common site, the wrists. The primary lesion consists of a flat-topped, polygonal, violaceous papule 2–6 mm in diameter. The characteristic shiny appearance of the individual papules is seen. This figure also illustrate the tendency for the solitary lesions to form confluent plaques. Exaggerated surface markings in the overlying skin (Wickham's striae) may also be evident but are difficult to appreciate. The forearms, the middle of the back, and the anterior surfaces of the lower extremities are other common locations. On the legs, lesions may become markedly hypertrophic and plaque-like. Diagnosis can sometimes be confirmed by the presence of oral lesions. Typically, there are small white papules in a reticular pattern on the buccal mucosa. The tongue, lips, and palate may also be involved.