Black toenails are essentially bruised toenails, and may have a blue coloration as well. The black or blue coloration is caused by internal bleeding.
Like regular bruises, black toenails can vary in severity from mild to extremely painful. Black toenails in particular are big indicators that the internal bleeding is bad, and the nail should be dealt with soon. The big toe is most commonly affected since it bears most of the weight of the body (and is also the biggest target for falling objects).
Black toenails (or blue toenails) are usually caused by direct trauma, such as dropping a heavy object on the toe or repetitive stress from running or dancing.
Dancers like ballerinas are especially vulnerable to black toenails, as the pressure put on their toes from the pointe work they have to do regularly can easily damage their nails. Adequate rest is essential for them, as the conditions can quickly get worse if the dancer insists on continuing to dance on a damaged toe.
Most cases of black toenails don’t require serious medical intervention, and mild cases may simply heal on their own. However, in cases where the entire nail has turned black like in the picture above, the blood inside may have to be drained in a procedure known as a subungal hematoma drainage. This procedure involves making a small hole in the nail so that the blood can be drained and cure the black toenails.
In more serious cases where the nail bed has been badly damaged such as in a particularly heavy impact, the nail may have to be removed so that the nail bed can heal. Recovery time will vary in each case.
In any case, we don’t recommend trying to deal with a serious case of black toenails yourself as you may introduce an infection that will make the situation worse. Consider seeking medical attention, or consulting a podiatrist to help with your black toenails.