Everyone gets bruises, but how many of us actually know what a bruise is? Here’s our guide to all things black and blue.
What is a bruise?
A bruise, also known as a contusion or ecchymosis, is an injury that results in purple, black or blue discolouration on the surface of the skin covering the injured area. The discolouration occurs when blood vessels known as capillaries burst as a result of a cut, bump, or trauma of some sort, and the blood gets trapped under the upper layers of your skin.
Bruises usually change colour over time and fade away gradually. Fresh trauma may appear red at first, before turning blue or black due to low oxygen levels at the site. Over time the bruise will turn green and then yellow as the injury heals and the haemoglobin in your blood starts to break down.
Types of bruises
Bruises can be categorised depending on where they occur. The three most common types of bruises are:
- Subcutaneous: Subcutaneous bruises occur under your skin
- Periosteal: Periosteal bruises or periosteal contusion are bruises that occur on your bones. Because a periosteum has nerve endings and a periosteal bruise is an injury to its blood vessels, you may feel quite a bit of pain in the injured area.
- Intramuscular: Intramuscular bruises occur when trauma causes blood to collect around your muscles. This can interfere with a muscle’s ability to function properly.
