History: Lichen spinulosus (LS) is a rare, idiopathic, follicular, keratotic dermatosis occurring mostly in children, adolescents and young adults.  Characterized by an acute development of symmetrically distributed follicular, keratotic papules that are sharply grouped in round to oval plaques varying in size from 2 cm to 6 cm, LS can appear on the extensor surfaces of elbows and knees, the neck, buttocks, abdomen and the trochanteric regions.