- Bumps and bruises facts
- What is a bruise?
- Why do bruises occur more frequently in some people than in others?
- What are symptoms and signs of a bruise, and why does it change color?
- What if the bruise doesn't get better or the area stays swollen?
- What are some less common causes of bruising, and what do they indicate?
- What is the treatment for bruising?
- What is the prognosis (outlook) for bruising?
Bumps and bruises facts
- A bruise is medically referred to as a contusion.
- Bruises occur when tiny blood vessels are damaged or broken.
- The injury required to produce a bruise varies with age and certain medications.
- Individual bruises change in appearance over time.
- Spontaneous bruising can indicate a serious bleeding tendency.
What is a bruise?
You fall off your bike, bang your shin on the coffee table (that you swore you would move months ago), or run into a wall and wake up with a bruise. What is a bruise, and what can you do about it? A bruise is caused when tiny blood vessels are damaged or broken as the result of trauma to the skin (be it bumping against something or hitting yourself with a hammer). The raised area of a bump or bruise results from blood leaking from these injured blood vessels into the tissues as well as from the body's response to the injury. A bruise is medically referred to as a contusion. A purplish, flat bruise that occurs when blood leaks out into the top layers of skin is referred to as an ecchymosis.
Why do bruises occur more frequently in some people than in others?
The injury required to produce a bruise varies with age. Bruising occurs more easily in the elderly because their capillaries are more fragile than those of young people. While it may take quite a bit of force to cause a bruise in a young child, even minor bumps and scrapes may cause extensive bruising in an elderly person. Blood vessels become more fragile as we age, and bruising may even occur without prior injury in the elderly.
The amount of bruising may also be affected by medications which interfere with blood clotting (and thus cause more bleeding into the skin or tissues). These drugs include many arthritis medications called nonsteroidal anti-inflammatories (for example, ibuprofen [Advil, Nuprin] and naproxen [Aleve]) and over-the-counter medications, such as aspirin. Warfarin (Coumadin) is often prescribed by doctors specifically to prevent clotting in patients who have had blood clots in their legs or heart. Warfarin can cause severe bruising, especially if the level of the medication becomes too high. Cortisone medications, such as prednisone, promote bruising by increasing the fragility of the tiny blood vessels in the skin.
Patients with inherited clotting problems (such as in hemophilia) or acquired clotting problems (such as in patients with liver diseases like cirrhosis) can develop extensive bruising, unexplained bruising, or even life-threatening bleeding. Sometimes spontaneous bruising is a sign of a bone marrow problem.
What are symptoms and signs of a bruise, and why does it change color?
Bruises can be associated with tenderness of the involved discolored area. Bruises change in appearance over time, and it may be possible to tell by looking at a bruise how old it is. When it first appears, a bruise will be reddish looking, reflecting the color of the blood in the skin. By one to two days, the reddish iron from the blood undergoes a change and the bruise will appear blue or purple. By day six, the color changes to green and by day eight to nine, the bruise will appear yellowish-brown. In general, the bruised area will be repaired by the body in two to three weeks after which the skin will return to normal.
What if the bruise doesn't get better or the area stays swollen?
On occasion, instead of going away, the area of a bruise will become firm and may actually start increasing in size. It may also continue to be painful. There are two major causes for this. First, if a large collection of blood is formed under the skin or in the muscle, instead of trying to clean up the area, the body may wall the blood off causing what is called a hematoma. A hematoma is nothing more than a small pool of blood that is walled off. This may need to be drained by your doctor.
A second and much less common problem occurs when the body deposits calcium, the material that makes up the majority of bone, in the area of injury. The area becomes tender and firm. This process is called heterotopic ossification or myositis ossificans.
This condition is diagnosed by X-ray and requires a trip to your doctor.
What are some less common causes of bruising, and what do they indicate?
The terminology describing different types of bruising often refers to not only their appearance but also to their cause. Petechiae are 1- to 3-millimeter accumulations of blood beneath the skin. These can appear like multiple tiny red dots on any part of the body (most commonly the legs). Most often these are multiple, and they can suggest that there is a serious health problem present. Examples of these are an infection of the valves of the heart (endocarditis) or abnormal function of the blood-clotting elements (platelets). Bruising around the navel (belly button) can be a result of bleeding within the abdomen. Bruising behind the ear (Battle's sign) can indicate that there is a skull fracture. Also, bruises that are raised, firm, multiple, and occur without any injury can be a sign of various types of "autoimmune" diseases (diseases in which the body attacks its own blood vessels). Each of these should be evaluated by a doctor.
What is the treatment for bruising?
There are a couple of things that you can do to prevent or minimize bruising after an injury. First, try a cold compress. Put ice in a plastic bag, wrap the bag in a towel (applying the ice directly to the skin can cause frostbite), and place it on the injured area. Commercial ice packs are also available, but a bag of frozen peas makes an excellent substitute. It molds to the shape of the injured area and can then be re-frozen and used again (but don't eat them!). The cold reduces the blood flow to the area and therefore limits bleeding into the skin and reduces the size of the bruise. The cold also decreases the inflammation in the area of the injury and limits swelling in this way as well. If possible, elevate the area above the level of the heart. The lower an extremity is below the heart, the more blood will flow to the area and increase the bleeding and swelling.
Avoid taking the medications listed above that can contribute to bruising. If you have any questions about whether or not your medication can contribute to bruising, ask your doctor or pharmacist. Do not stop any prescription medications without first contacting your doctor.
Finally, pressure applied to the area (by hand, not with tourniquets) can reduce bleeding.
People who take medicines that reduce clotting ("blood thinners") or have clotting abnormalities should seek the advice of a physician immediately, as should the elderly or those who have experienced significantly severe trauma.
Medically reviewed by A Board Certified Family Practice Physician
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.