Picture of Lichen Planus 2
Lichen planus (LP) is an inflammatory disorder of the skin and mucous membranes with no known cause. It appears as pruritic, violaceous papules and plaques most commonly found on the wrists, lower back, and ankles. There is a small percentage of patients that develop lichen planus on the nails as shown here.
Text Source: National Library of Medicine, National Center of Biotechnology Information