One in every 1,000 runner gets a black toenail

Tuesday, 03 November 2015 690 Views 0 Comments
One in every 1,000 runner gets a black toenail

By Shailja Kaushik

Black toenails are very common in athletes, especially runners…. One in every 1000 runner gets a black toenails.

What cause black toenails?

If the shoes are small in size or the person is running downhill, the toe repeatedly rubs against the inside of the shoe, this trauma to the toenail results in collection of blood underneath the nail and causes it to discolour. This discoloration is known as subungual hematoma.


Black toenails are caused by any of the following reasons:

  • Injury. For instance, a heavy object lands on the toe
  • Repetition of the above trauma
  • Poorly fitted shoes
  • Fungal infections


Although symptoms may not always be present; most commonly black toenails are associated with discoloration. Other than just the change in color, the runner with black toenails may feel pressure, intense pain and discomfort. Sometimes, there is also a foul smell and discharge from the underside of the nail.

Black toenails are a rather unpleasant sight. Often, the nail separates from the bed and chips off within days.


To prevent black toenails, follow these guidelines[i]:

  • Make sure your running shoes fit properly. Test them at the end of the day when your feet are swollen. Ensure that there is a distance of a thumbnail between your longest toe, (which could be your second toe), and the mouth of the shoe
  • Make sure your toenails are trimmed before you run. Sometimes an extra long nail can hit the front of the shoe and cause bleeding beneath the nail
  • Make sure your insole or orthotic is not slippery. Sometimes the slippery insoles make the foot slide forward and the toe hits the front. Try putting a non slippery covering over your insole or orthotic.

Here are some other useful tips:

  • Be careful while moving heavy objects
  • Avoid walking barefoot
  • Keep your feet and toenails clean and dry
  • Wear clean socks and shoes
  • Don’t put-off visiting a doctor if you notice any discolouration or feel pain in the area.


Black toenails usually fall off, and re-grow on their own. If there is no pus, fever or any other sign of infection, then there is no need to seek medical attention. When the discoloration spreads and covers more than 50% of the toenail, you should see a doctor. The nail bed might be lacerated or the bone beneath the nail may be exposed. In such conditions, it is critical to check with a doctor because it might lead to bone infection which is dangerous and could even call for amputation.

Depending on the severity of the condition, your doctor will recommend the treatment. In many cases, the nail may be left to heal on its own. In case there is any cause for concern, the nail will be removed to examine the nail bed after administration of local anaesthesia. Presence of laceration requires washing and suturing the area. If there is only blood collection, then it can be drained to release the pressure and pain. Sometimes, a small hole is created in the nail to allow the fluid to drain.

Even after the treatment, the discoloured toenail may not re-grow like before. Therefore, it is suggested to visit a doctor as soon as you notice the slightest discoloration. On an average, black toenails take a few months to heal completely.


Steven I. Subotnick. Sports & Exercise Injuries. Conventional, Homeopathic and Alternative Treatment. North Atlantic Books, 1991.

Stephanie L. Tourles. Natural Foot Care: Herbal Treatment, Massage and Exercises for Healthy Feet. Storey Publishing, 2012.

[i] Lewis G. Maharam, MD. Running Doc’s Guide to Healthy Running. How to Fix Injuries, Stay Active and Run Pain-Free. VeloPress, 2013.

(Dr. Rohan Habbu is an Orthopedic Hand, Nerve & upper Extremity Surgeon. He has done Fellowship in Arthroscopy & Sports Surgery and is an avid runner. To know more, reach out to him on or +91 982017 13941)

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