03/03/2026
Black toenails are common in runners, usually resulting from repeated trauma to a toenail inside the shoe. While running, the toes strike the front or roof of the toe box, especially on downhill routes or long distances. This can cause bleeding beneath the nail, called a subungual hematoma. The drie...
Read more: https://www.pinnaclefootcenters.com/component/k2/item/715-causes-of-black-toenails-in-runners.html