Transverse depression/line/furrow in nail plate – no discolouration. Due to sudden arrest of nail growth, generally due to trauma or systemic condition (with a febrile illness). Multiple incidents/events multiple Beau’s lines. Appear proximally and grow out nail growth is 3 months in young adult and 4 months in older person can approximately date episode of illness/trauma
Been reported as associated with severe dysmenorrhoea, arsenic poisoning, eczema, diabetes mellitus.