Bruises are a part of life. If you use your body, it's going to get bruised at some point. By the time you notice a bruise, though, it's already started to heal.
A bruise, also called a contusion or a hematoma, is nothing more than bleeding that occurs under your skin or in the soft tissue beneath it. The bleeding occurs because trauma to the body has caused blood vessels to break. The blood has nowhere to go and gets trapped under the skin. There are three types of bruises: Subcutaneous bruises that occur beneath the skin, intermuscular bruises that occur inside the muscle, and periosteal bruises that occur on the surface of the bone. Bone bruises are the most painful and take the longest to heal.
As a bruise heals, it changes color until it disappears. Bruises typically change color in a progression from a reddish blush, to a gradually darkening blue or purple, followed by green, and finally a yellow-brown color.
This color change occurs because white blood cells are removing the decayed blood products little by little. Different components of the blood have different colors, and these colors in turn lend color to the bruise. Green, for example, represents a component called biliverdin. Yellow-brown represents bilirubin.
The closer the broken blood vessels are to the surface, the sooner the bruise appears, and the more intense its colors will be.
Most small bruises disappear within seven days, and larger ones can take months to heal. Bruises may last longer in elderly adults, however, because restricted circulation slows the removal of the decaying blood components. This may be particularly true in the legs, where circulation may be restricted.
Some people bruise more easily than others. You're more likely to be black-and-blue if you regularly take anticoagulants or aspirin, both of which interfere with blood clotting. If the blood doesn't clot as easily, more of it will leak out under the skin when trauma occurs.
To treat a bruise, the first step is to apply ice, but not for more than 15 minutes at a time. Place the ice in a cloth or towel. Do not place ice directly on the skin. Ice numbs the pain and slows down the bleeding. After two days, you can begin to apply heat. This speeds recovery by increasing circulation in the affected area. If you can, elevate the area that is bruised.
It may also help to rest the injured body part. If it is painful, take acetaminophen or ibuprofen if you don't have allergies to these medications.
When does a bruise require medical attention?
If you feel a large amount of pressure in the bruised area of your body and it is quite painful, see your health care provider immediately. You may have what is called compartment syndrome. This is a condition in which the muscle swells more than the surrounding tissues can expand. Compartment syndrome may require surgery. It is an emergency and should be treated right away.
If you have a bruise, but you don’t recall being hit or injured where the bruise appears.
If the pain is out of proportion to what you might expect from the injury.
If the bruise is larger than what you'd expect from the injury.
If the pain worsens; the pain should lessen with time.
People with a condition called hemophilia (blood disorder), or people taking anticoagulants (blood thinners), should probably talk to their health care provider if they get a large bruise. If you seem to develop bruises in the course of your normal activities, without a related increase in falls or bumps, you should also check with your provider.