Bruises are one of the most common and visible injuries, often caused by intense or repeated contact of the skin with another object. Bruises frequently result from falls, accidents or sports injuries, but they may also be indicative of an underlying medical condition. For this reason, parents of children who bruise easily or experience regular, severe or unexplained bruising should seek medical treatment.
What is a bruise?
A bruise is a form of internal bleeding, known medically as a contusion. It is caused when muscle fibres, capillaries and venules (small veins) under the skin are damaged but the skin itself remains intact, causing blood to seep into the surrounding tissue.
The skin around a bruise appears discoloured and is usually more sensitive to touch. Sometimes even light contact will cause pain due to increased pressure on nerve endings within the region, meaning that the body is more receptive to other forms of pressure applied to the area. Bruises typically resolve after approximately two weeks, though additional damage to the area may prolong the healing process.
One of the greatest fascinations with bruises is their change of colour, this is the result of chemical changes in the blood beneath the skin.
Initially bruises appear as red spots, reflecting new blood seeping into the area. As the hemoglobin (a key component in red blood cells) breaks down, it creates new colours in the skin. Firstly a black, blue or purple colour followed by green, yellow and then finally golden brown as the bruise heals. It is quite common for a bruise to have multiple colours at once as the hemoglobin breaks down at different rates in the skin.
Treatment of bruises
Most minor bruises will resolve by themselves over time (normally around two weeks), but it is best to avoid damaging (bumping or prodding) the area further to allow it to heal.
The application of a cold compress (ice or ice pack) and raising the affected area immediately following an injury - and for up to 48 hours thereafter - can help to reduce blood flow and thus reduce swelling and bruising. Painkillers, such as paracetamol or ibuprofen, can help to relieve pain caused by more serious bruising.
Extensive bruising could indicate that greater damage has been caused or that an underlying medical condition is contributing to the bruise. In these instances, it is best to seek medical assistance.
Causes of bruising
Certain regular use of medications which thin the blood, including aspirin, can contribute to increased blood flow and more severe bruising. Consult a medical professional if you’re unsure about the effects of a medication.
A number of diseases, including hemophilia, leukemia, thrombocytopenia (low blood platelets), autoimmune diseases (lupus and rheumatoid arthritis), infectious diseases (measles and meningitis) and rarer blood disorders can all cause children to bruise more easily.
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Robin, S 2011, ‘Diseases That Cause Easy Bruising in Children’, LIVESTRONG.COM, retrieved 18 May 2011, <http://www.livestrong.com/article/105204-diseases-cause-easy-bruising-children/>.
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MedlinePlus 2011, ‘Bruise’, retrieved 18 May 2011, <http://www.nlm.nih.gov/medlineplus/ency/article/007213.htm>.