A hematoma is the result of a traumatic injury to your skin or the tissues underneath your skin.

When blood vessels under your skin are damaged and leak, the blood pools and results in a bruise. A hematoma forms as your blood clots, resulting in swelling and pain.

Hematomas can occur anywhere in your body, including your leg.

Although hematomas can show up elsewhere, if they appear on your leg, it’s usually due to injury such as a blow to your leg from a fall or an encounter with a blunt object.

A hematoma can also form after you have certain leg surgeries.

Your potential for hematoma could increase if you’re taking medication that thins your blood, such as:

Your potential could also increase if you are suffering from a viral infection, such as:

Other conditions that can heighten your risk of hematoma include:

The primary symptoms of a leg hematoma are:

  • discoloration from the blood under your skin
  • swelling
  • pain

Usually the extent of the discoloration and swelling reflect the severity of the injury. Fracturing your thigh bone (femur) is commonly associated with a significant amount of bleeding and will often result in a large hematoma.

Hematomas usually clear on their own, slowly getting smaller over time as the accumulated blood is absorbed. It might take months for a large hematoma to be fully absorbed.

Commonly, a leg hematoma is treated with:

  • cold compress or ice pack application for 20 to 30 minutes for the 48 hours following injury to reduce swelling
  • rest
  • elevating your foot higher than your heart
  • light compression with a wrapped bandage
  • pain medication such as acetaminophen (Tylenol)
  • heat for 10 minutes three times daily for 48 hours following the injury to increase blood flow

If you’re treating a hematoma at home, do not take aspirin or ibuprofen (Advil, Motrin). These over-the-counter drugs aren’t recommended because they can slow blood clotting.

Surgery

If you have a hematoma over your shinbone, your doctor may recommend surgery. If you have a large hematoma that doesn’t go away for several days following your injury, your doctor might suggest that it be drained.

If you bruise your leg and the bruise becomes swollen and painful, you could have a hematoma. It could indicate an injury that is — or complications that are — more severe than you think, especially if the bruise doesn’t improve over a week or two. See your doctor so they can examine your leg and make a treatment recommendation. If you think you’ve broken your leg, be sure to get emergency medical attention.