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A member asked:

Hello i have i black line on my left thumb and i want to know why?

A doctor has provided 1 answer
Dr. Keshab Paudel answered

Specializes in Internal Medicine

Please see below: Usually this is traumatic in origin but happens in some medical conditions as well. If you have a psoriasis, you can see some changes in nails. Similarly, there are few other conditions we can see these nail findings. If you have this line for long time , its good to see a doctor.

Answered 4/8/2014

4.2k views

Thank

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