The most common culprit for black nails, repetitive trauma can result from running, or from wearing any type of ill-fitting footwear. If a black nail crops up shortly after a workout or a day spent in too-tight or too-loose shoes, this is likely the cause. Repetitive trauma ranges from mild (i.e. a small, painless, black-and-blue discoloration beneath the nail), to severe (i.e. large, bloody blisters between your nail and nail plate), explains Jacqueline Sutera, DPM and spokesperson for the American Podiatric Medical Association.
|Dr. Jacqueline Sutera
In mild cases, no treatment is needed and the black nail will simply grow out. In severe cases, beneath-the-nail blisters can cause the nail to detach—either partially or fully—from the nail plate.
Source: Jenny McCoy for Runner's World via Prevention [4/12/17]
Courtesy of Barry Block, editor of PMP News.
Brought to you by Doctor John A. Hardy, owner of Toronto's Foot Clinic, Academy Foot and Orthotic Clinics.