Bruises (or contusions) can occur all over the body for a variety of reasons, the main one being your body coming into contact with another person or object. If the collision is severe enough, the blood vessels break. This causes red blood cells to leak into the tissues under the skin, causing swelling, discolouration and pain.
The skin bruises more easily the older it gets. This is because the collagen that cushions the skin breaks down, leaving the blood vessels more vulnerable.
As the body metabolises the red blood cells in the skin, the bruise goes through an interesting range of colours. This is due to the chemical changes in the haemoglobin of the red blood cells, breaking down into bilirubin1 so it can be reabsorbed into the bloodstream. Depending on the force that caused the bruise, and the size, an average bruise will last approximately two weeks.
- Day one - reddish and/or purple
- Day three - blue and/or blackish
- Day six - green and yellow
- Day eight - yellow and brown
- Day ten - light brown
- Day fourteen - gone
If the bruise does not disappear within two weeks, possibly becoming larger or more painful, it is likely that it has become a haematoma. This is when the body 'walls off' the area instead of trying to clear it, leaving a pool of blood under the skin. Haematomas can heal themselves, but they should be checked by a doctor or nurse.
Some medications can cause the skin to bruise more easily. These include non-steroidal anti-inflammatories such as ibuprofen and Advil, often prescribed for arthritis (Aspirin can have a similar effect). Warfarin, the drug prescribed to patients to prevent blood clots can cause severe bruises. Cortisone medications make the blood vessels very fragile, and so bruises can occur after even minor bumps. Patients with clotting problems such as haemophilia or cirrhosis of the liver can develop extensive bruising.
There are a few things that can be done to keep the bruising to a minimum; a cold compress on the area can help by reducing the size of the blood vessels, so preventing them from leaking so much; this also helps to relieve the swelling. If a tincture of witch hazel is added to the cold compress it will give additional relief. As with any broken blood vessels, raising the bruise above the level of the heart as it forms can slow bleeding.
Cream containing vitamin K can be applied to the skin to help fade and clear bruises. It helps the blood vessels to heal themselves, and supports the body's ability to reabsorb blood into surrounding tissue.
Dark swollen bruises will benefit from arnica, a plant that has pain relieving and healing properties. Applied as a cream or gel to the bruise every three hours will encourage healing, and help improve the swelling, stiffness and discolouration.
1 Red blood cells contain haemoglobin which carries oxygen. Once the red blood cell gets worn out, part of the haemoglobin is recycled and part of it is turned into billirubin by the liver. This is the cause of the yellow colour of the bruise, and eventually leaves the body as a waste product during the digestive process.