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Pressure ulcers: Overview

Last Update: November 15, 2018; Next update: 2021.


Some people inevitably spend a lot of time in a sitting or lying position. Most of them keep moving and shifting a little, consciously or subconsciously. But people who are extremely weak, paralyzed or unconscious may instead sit or lie motionless in the same position for a very long time. This puts them at greater risk of developing pressure ulcers (also called bedsores or pressure sores).

These are open wounds caused by persistent pressure on the skin from the outside. They can be very painful and usually take a long time to heal.


Pressure ulcers nearly always develop in places where there are bones right under the skin. This includes the tailbone, heels, hips, shoulder blades, ankles, elbows, ears, and the back of your head.

If your body weight constantly “squashes” your skin in these places when you are sitting or lying, not enough blood can get through to provide oxygen and nutrients. The skin becomes thinner, and it may gradually die over time. This creates a wound that is especially painful when you sit or lie on it.

Illustration: Pressure ulcers: Places where they commonly develop while lying on your side
Illustration: Pressure ulcers: Places where they commonly develop while lying on your back

Pressure ulcers: Places where they commonly develop in people lying down

Illustration: Pressure ulcers: Places where they commonly develop while sitting in a wheelchair
Illustration: Pressure ulcers: Places where they commonly develop while sitting

Pressure ulcers: Places where they commonly develop in people sitting

Risk factors

People who are healthy quickly notice pain whenever there is too much pressure on one part of their body. But some diseases can affect how you perceive pain or increase your risk of wounds developing:

  • People who are paralyzed often don't sense pressure or pain in the parts of their body that are affected.
  • People who have had diabetes for many years sometimes feel less pain and may not notice if there is too much pressure on one part of their body. Diabetes can also affect the flow of blood through the body.
  • Circulation disorders, possibly due to narrowed blood vessels (arteriosclerosis), make it even more difficult for blood to reach vulnerable areas of skin.
  • Malnutrition is an additional risk factor for people who are bedridden. This is because people who hardly have any body fat and drink and eat very little have thinner and less resistant skin, with poor blood circulation.
  • Friction and shear (the forces caused by two layers of skin rubbing against each other) can damage the skin further. This might happen when people who are confined to their bed are moved, and their skin is pulled over the mattress or sheets. The movement can push the different layers of skin against each other: The top layer is stopped from moving by friction with the sheets, but this doesn't affect the other layers. This can cause redness and superficial skin injuries.
  • Incontinence: Skin that is exposed to urine (pee), feces (poop) or sweat for hours is more prone to irritation and damage. This can happen to people who are often in wet diapers for longer periods of time. The skin that has softened up is more likely to become damaged.

If someone has already had a pressure ulcer in the past, they are more likely to develop another one in the same place. This makes it all the more important to try to stop pressure ulcers from developing in the first place.


Pressure ulcers can be very painful and also emotionally distressing. Open, poorly healing wounds also act as gateways for germs, which may lead to an infection. If germs spread further into the body they may cause blood poisoning (septicemia).


Some people are able to check their own skin for early signs of pressure ulcers, for example with the help of a mirror. If they have been in a situation where they could hardly move or were not able to move at all for a longer time, they often know the warning signs. People who are too weak to turn around, sit up or stand up on their own have to rely on help from others to check any at-risk areas of their body, though. These areas are usually on the back of their body, such as on their heels or bottom.

Nurses and doctors often use the following classification system to assess the severity of a pressure ulcer:

  • Stage 1: The skin isn’t damaged but it is reddened, even when no pressure is applied. It might feel warmer or colder, more sensitive to pain, or softer or harder than the surrounding tissue.
  • Stage 2: The upper layers of the skin are damaged, and there may be a blister, scrape or bruise, for instance.
  • Stage 3: All of the skin layers are damaged and there is a deep wound that may even reach down to the fat layer of the skin. Slough (dead tissue and pus) cover the wound; some parts of the skin may have died (necrosis).
  • Stage 4: The skin and much of the surrounding tissue is damaged and has died. The muscles, tendons and bones may be damaged as well. The wound often has slough on it or is covered by a scab.

From stage 2 onwards, it may be necessary to take a swab, blood or tissue sample if doctors think that the sore might be infected with bacteria.


If someone has to sit or lie down without moving for a long time – even if just for a few days – it's important to reduce the pressure on the most at-risk parts of their body through regular repositioning and turning. Special supportive surfaces can also help to relieve some of the pressure. For instance, there are special mattresses or overlays like a sheepskin.

Regularly checking the more vulnerable body areas will allow you to react faster if there are any early signs of a pressure ulcer. It is important to take care to avoid friction and shear forces as much as possible when repositioning and assisting someone. For instance, don't pull them across the mattress or sheets. Moisturizers can be used to help with dry skin. If the person is incontinent, their incontinence pads or diapers need to be changed regularly too.

It's also important to make sure that the person gets enough to drink and eats a balanced diet: Not getting enough fluids or malnutrition can weaken the skin even more.


The most appropriate treatment will depend on the type and severity of the pressure ulcer. The goal of treatment is always to prevent the pressure ulcer from being subjected to continuing pressure. Positioning aids, special mattresses, and regular repositioning and movement help to relieve the pressure on the affected parts of the body.

Many different types of wound dressings can be used for pressure sores. Every time the dressing is changed, the wound is cleaned with tap water or a saline (salt) solution. For stage 3 and 4 wounds, a technique called debridement is used as well to remove dead tissue. Debridement involves using tweezers or a scalpel to remove dead cells. Most pressure sores heal completely even without surgery. The treatment can take a long time, though.

When cleaning the ulcer and changing dressings, pain can be prevented with local anesthetics or wound dressings that contain ibuprofen. They can provide short-term pain relief. Oral medication like acetaminophen (paracetamol) or ibuprofen tablets can help relieve mild to moderate pain. If these don’t provide enough relief, doctors can prescribe stronger painkillers.

Everyday life

Moving and changing your position as much as possible can help to prevent pressure ulcers. Caregivers can keep on encouraging you to do so. It's important to relieve the pressure on at-risk areas of skin quickly and to show them to a doctor or nurse.

People who have pressure ulcers may feel very uncomfortable. In addition to the pain, they may feel embarrassed. So good support is needed on both personal and medical levels.

Family members can also learn various repositioning techniques in special caregiving courses. In Germany and other countries, health insurers or long-term care insurers cover the costs of many of the aids needed at home or may lend things like nursing beds. Many cities also have information centers for caregivers, offering help and advice concerning issues related to pressure ulcer prevention.

Further information

When people are ill or need medical advice, they usually go to see their family doctor first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.


© IQWiG (Institute for Quality and Efficiency in Health Care)
Bookshelf ID: NBK326428


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