What is a pressure sore?

A pressure sore is an ulcer caused by pressure and/or shearing force, often over bony areas. Pressure sores are graded in four stages, with two more categories for sores whose depth can’t be judged yet.

A pressure sore is an ulcer caused by pressure and/or shearing force. You may also hear it called a pressure ulcer, pressure sore, pressure injury or decubitus ulcer. These all describe the same thing.

Pressure ulcers happen when skin and deeper tissue are under pressure or rubbing (shear) for too long, often over bony areas such as the heels, tailbone and hips. There’s also a cause people rarely expect: some pressure injuries can be caused by medical devices, for example tubing, masks or casts.

Some people are at higher risk: people who cannot change position, who have reduced sensation, who have moist skin from incontinence or sweating, who have poor nutrition, or who are very unwell.

Pressure sores are grouped by how severe the symptoms are. A stage I sore is a reddened, painful area on the skin that does not turn white when pressed. At stage II, the skin blisters or forms an open sore. At stage III, it develops an open, sunken hole called a crater or ulcer, and the tissue below the skin is damaged. At stage IV, the ulcer is so deep that there is damage to the muscle and bone, and sometimes to tendons and joints.

Two kinds sit outside that scale. A sore covered in dead skin that is yellow, tan, green or brown is called unstageable, because the dead skin makes it hard to tell how deep the sore is. A deep tissue injury is a pressure sore developing in the tissue deep below the skin. The area may be dark purple or maroon, and it can quickly become a stage III or IV sore.

Are pressure sores unavoidable? No. Many pressure ulcers can be prevented with a prevention plan.

What to watch for

Contact your provider right away if you develop blisters, an open sore, or any signs of infection, such as a foul odor from the sore, pus coming out of the sore, redness and tenderness around the sore, skin close to the sore that is warm or swollen, or fever.

A deep tissue injury — dark purple or maroon, with the skin still intact — can become a stage III or IV pressure sore quickly.

Some pressure injuries are caused by medical devices such as tubing, masks or casts. These are easy to overlook.

Wound Wizard is general education and can’t assess your wound or your situation. Your own clinician is the right person to ask about your wound.

What we look at

  • Examining the area and the skin over it
  • Identifying the stage, or whether it can be staged yet
  • Finding and relieving the source of pressure
  • Setting a prevention and monitoring plan

Sources

  1. Wound Q&A for patients and relatives — European Wound Management Association https://ewma.org/resources-for-patients-private-carers/wound-qa-for-patients-and-relatives/
  2. How to care for pressure sores — MedlinePlus, U.S. National Library of Medicine https://www.medlineplus.gov/ency/patientinstructions/000740.htm