There are small short black lines in the fingernails.

There are small short black lines under the nails, which may be considered as congestion under the nails. It is more common in the outer end of the nails. It can be punctiform or cord-shaped, often related to traumatic collisions, such as accidental extrusion or violent blows. Due to the fragility of capillaries under the nails, subcutaneous bleeding will occur. It can be scalded with warm water every night to help promote absorption and improve local blood circulation. Sometimes also need to be alert whether it is nail mother mole, it is originated from the nail root melanin cell proliferation, has little impact on health, but if the change is large in a short time, need to seek medical examination in time.