Black Mark On Toes. Big Toe Nail Has Fallen Frequently. Do Regular Running. Is This A Sign Of Melanoma?
Thanks for posting your query.
Any black line under your toe nail which doesn't grow out with it and you are sure that it is not caused by trauma needs to be evaluated. The cause needs to be confirmed now without wasting time on speculation. This will save you unnecessary stress later on.
According to your description, I feel that trauma or a fungal infection is the more likely cause in your case.
So I suggest that you consult a dermatologist who can thoroughly evaluate you to come to an exact diagnosis and treat accordingly. You shouldn't self medicate or keep delaying the visit to the dermatologist since you are already developing it on your second toe.
There are few signs of melanoma which should be checked in case of any black spot on the nailbed or toes.
1. Assymetrical, which means a melanoma is not symmetrical in shape unlike a mole which is more rounded or symmetrical
2. Irregular border i.e. it doesn't have a smooth border
3. Colour changes, it is usually a combination of blue black and brown
4. Size is usually more than 5 mm
These are signs which point more in favour of melanoma, so if you have any of these, you should consult a foot surgeon.
Hope I have answered your query.
I'll be available for any follow up queries. Please accept my answer of you have no further queries.
Regards