These black lines on fingernails may look like bruising or internal coloring - not like you just accidentally created an edgy ...

Michelle Tagliamonte, 58, was getting a manicure when she noticed the black lines on her thumb, which signaled the start of a ...

Longitudinal ridging, which is clinically known as onychorrhexis, occurs on the nails and may appear as vertical striations or lines that originate from the base of the fingernail and continue to ...