Subungal Hematoma

Both toenails and fingernails are often subjected to being hit and pinched, often repeatedly. Such an injury can lead to the formation of a hematoma under the nail – or "black nail". This condition is usually very painful because of the pressure created by the blood pressing against the nail.

Signs and Symptoms

  • Throbbing pain caused by pressure from the bleeding which builds up under the nail.
  • Discolouration underneath nail.

On-Site Management

ICE. Place the nail in an ice bath. Once the throbbing has been reduced, the pressure under the nail can be released using one of the following methods:

Method 1. The fingernail should first be treated with an antiseptic solution. Then using a sharp object such as a sterile needle, small-gauge drill, or paper clip, make a small hole in the nail using a rotary action.

Method 2. Bore a hole through the middle of the nail using a paperclip that has been heated until red hot and placed against the nail using slight pressure. This procedure is simple and usually painless. The nail will usually fall off in a few weeks. There is often temptation to remove an only slightly attached nail, however, this results in greater pain and should be avoided. The nail area should be kept clean and monitored for infection.

Return to Activity

The athlete can return if they feel comfortable enough to play.


There is no real prevention for a subungal hematoma, but wearing properly fitted footwear can help prevent them in some circumstances.

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