What causes a pressure ulcer?
Pressure ulcers are caused by the pressure from the weight of your body pressing down on your skin. They usually occur when a bony prominence is pressed against a surface such as a chair or a bed. This compresses the skin and the underlying tissues and can also damage blood vessels. Friction (rubbing) of your skin can also play a part in the formation of a pressure ulcer. Friction can happen, for example, if you are dragged across a surface such as a bed. If you are spending long periods in bed or in a chair, you may slide down and need to be pulled back up again by someone else (or you may be able to pull yourself back up). However, as these sliding and pulling movements happen, the layers of your skin also slide over each other, as well as over the underlying tissues. These sliding or ‘shearing’ forces can also contribute to pressure ulcer formation. Changes to the skin as it ages may make this sliding of the skin more likely. A lot of moisture around the skin (for example if you hav
