The Center for Podiatric Care and Sports Medicine

Runner’s Nails: What To Do About The Black & Blue

Posted by on Monday, September 2nd, 2013


Any avid runner knows that the sport is not always so glamorous. There are some days where we’re drowning in tears when one of our black toenails finally prepares to fall off. The average person may call this a “black and blue toenail” or “runner’s toe,” whereas a geek (or your non-geeky podiatrist!) might call it a “subungual hematoma” — which is a fancy way of saying “bruised toenail.” No matter what you call the condition, it ain’t pretty! The good news is: we know how to fix it!

What Causes A Subungual Hematoma?

The start / stop motions of running can cause broken blood vessels and bruised tissue over time. Toenail bruises often result from repetitive trauma or wearing shoes that are too tight. You may have been breaking in a new pair of runners… or you may be running a marathon, which causes a lot of repetitive stress to the nail. The discoloration occurs when blood collects underneath the nail bed. The condition doesn’t always hurt, but throbbing pain is fairly common. In very rare cases, it may not be Runner’s Toe at all; the toenail itself may be affected by fungus and turn black or the patient has a malignant type of melanoma.

How Can I Treat Runner’s Toe At Home?

First, find a shoe with a bigger toe box. Secondly, be sure you soak your feet in Epsom salts to get rid of debris and dead tissue. Leave the damaged nail on for as long as possible, allowing it to fall off naturally, so the new nail grows back in a normal position. Apply antifungal medication to prevent fungal infection, but avoid wearing Band-Aids for long periods of time (which can trap moisture in and actually promote fungal growth.) Recovery time will likely take several months.

When Should I See A Doctor About My Bruised Toenail?

Sometimes black toenails fall off and regenerate on their own. Medical attention should be sought if you are suffering the symptoms of an infection — such as: fever, chills, odor and/or discharge. You should also seek a doctor’s help if the discoloration affects 25% or more of your nail. If the nail bed is lacerated, you may have a portal to infection left vulnerable. The worst case scenario would be a bone infection (osteomyelitis), which will require long-term antibiotics and could possibly result in amputation. Yikes!

In some cases, oral antibiotics will be prescribed. A doctor may need to drain the fluid using a drill, needle or cautery. Other times, he may need to remove the nail and apply a bandage for you. We know it sounds gruesome. It’s enough to make pro NFL football players squirm in their seats. Yet, these methods are only recommended when absolutely necessary to protect your health. We promise it doesn’t feel nearly as bad as it sounds!


If you have any foot problems or pain, contact The Center for Podiatric Care and Sports MedicineDr. Josef J. GeldwertDr. Katherine Lai, Dr. Ryan Minara and Dr. Mariola Rivera have helped thousands of people get back on their feet. Unfortunately, we cannot give diagnoses or treatment advice online. Please make an appointment to see us if you live in the NY metropolitan area or seek out a podiatrist in your area.