This article describes where pressure ulcers form and how to tell if you are at risk of getting a pressure ulcer. It also lists steps to take to prevent them or keep them from getting worse, and suggests how to work effectively with your health care team. Where Pressure Ulcers Form Pressure ulcers form where bone causes the greatest force on the skin and tissue and squeezes them against an outside surface. This may be where bony parts of the body press against other body parts, a mattress, or a chair. In people in chairs or wheelchairs, the exact spot where pressure ulcers form depends on the sitting position.
Pressure ulcers can also form on the knees, ankles, shoulder blades, back of the head, and spine.
Nerves normally tell the body when to move to relieve pressure on the skin. Persons in bed who are unable to move may get pressure ulcers after as little as 1-2 hours. Persons who sit in chairs and who cannot move can get pressure ulcers in even less time because the force on the skin is greater. Your Risk Confinement to bed or a chair, being unable to move, loss of bowel or bladder control, poor nutrition, and lowered mental awareness are risk factors that increase your chance of getting pressure ulcers. Your risk results from the number and seriousness of the risk factors that apply to you.