Lichen striatus is a benign, self-limiting linear dermatosis that develops along the lines of Blaschko (lines corresponding to developmental growth patterns during embryogenesis) [1]. Lichen striatus is frequently asymptomatic, though cutaneous lesions may be associated with mild pruritus [2]. Lichen striatus presents acutely and self-resolves. Lichen striatus rarely affects the nail unit and is characterized by longitudinal fissuring and onycholysis, typically limited to the lateral portion of the nail plate [1]. There is often concurrent cutaneous involvement with nail changes, or cutaneous lesions may occur before or after nail involvement [1]. Though less frequent, nail dystrophy without skin involvement may occur. Etiology is thought to be due to cutaneous mosaicism, in which somatic mutations result in abnormal keratinocyte clones that remain silent until a triggering event occurs [3]. A trigger interrupts immunologic tolerance and induces expression of novel membrane antigens, resulting in a self-limited autoimmune CD8+ T lymphocyte-mediated response [4, 5]. Multiple triggers have been hypothesized to play a role, including trauma, viral infections, vaccines, pregnancy, and hypersensitivity reactions [6–11]. Pathophysiologically, there is an inflammatory process in the nail matrix resulting in abnormal keratin synthesis [12].