Page last updated:
5th June 2024

Pressure ulcers

Overview – pressure ulcers can be found on legs, ankles or heels

Pressure ulcers (also known as pressure sores or bedsores) are injuries to the skin and underlying tissue, primarily caused by prolonged pressure on the skin.

They can happen to anyone, but usually affect people confined to bed or who sit in a chair or wheelchair for long periods of time.

Pressure ulcers should be diagnosed and assessed by healthcare professionals with the necessary skills and competencies. 

Symptoms – what are the early signs and symptoms of pressure ulcers?

Pressure ulcers can affect any part of the body that’s put under pressure. They are most common on bony parts of the body, such as the heels and ankles. They often develop gradually, but can sometimes form in a few hours, especially in an immobile, poorly person.

Early symptoms of a pressure ulcer

  • An area of non-blanchable erythema (redness). Be aware that non-blanchable erythema (redness) may present as colour changes or discolouration, particularly in darker skin tones or types. Part of the skin becoming discoloured – people with pale skin tend to get red patches, while people with dark skin tend to get purple or blue patches
  • Marked localised skin changes
  • A patch of skin that feels warm, spongy or hard
  • Pain or itchiness in the affected area
  • A wound of varying severity on an anatomical site that is known (or suspected) to have previously been exposed to significant unrelieved pressure (NICE guidelines, 2024)
  • Whole or partial loss of sensation in the affected area

A podiatrist or nurse may call a pressure ulcer at this stage a category 1 pressure ulcer.

Later symptoms

The skin may not be broken at first, but if the pressure ulcer gets worse, it can form:

  • An open wound or blister – a category 2 pressure ulcer
  • A deep wound that reaches the deeper layers of the skin – a category 3 pressure ulcer
  • A very deep wound that may reach the muscle and bone – a category 4 pressure ulcer
Nerys' story
Read Nerys' pressure ulcer story – “A life-changing road traffic accident took me to rock bottom. Now I’m about to swim the English Channel”

Causes – what can cause pressure ulcers?

Pressure ulcers are caused by pressure, or pressure in combination with shear forces 

  • The duration and intensity of pressure are important: tissue damage may occur as a result of relatively short exposures to intense pressure or prolonged exposure to lower levels of pressure. Pressure forces are distributed throughout the soft tissue, the extent depending on the mechanical properties of both the soft tissues and any external support surface or device
  • Shear forces, typically generated when people slide down in a bed or chair, may cause stretching and tearing of small blood vessels and contribute to pressure-induced skin damage
  • Friction and moisture can also contribute to the development of pressure ulcers:
    • Friction can cause superficial injuries, including skin tears, which could facilitate the transmission of pressure to the deeper tissues
    • Moisture decreases the stiffness of the stratum corneum and increases the coefficient of friction so that skin is more adherent to the contact surface, resulting in greater shear forces being transmitted to deeper tissues. Additionally, moisture can cause moisture-associated dermatitis, which could also facilitate the transmission of pressure to the deeper tissues

Pressure ulcers can occur due to the forces of a person’s body weight or as a result of externally exerted forces, such as those applied by a medical device and/or other objects [EPUAP/NPIAP/PPPIA, 2019Gefen, 2020]

  • When a person is immobilised for extended periods, for example, in the supine position, the pressure and shear forces cause tissue deformation, inflammatory oedema, and ischaemia, leading to pressure ulceration in bony anatomical sites, such as the sacrum, ischium, elbows, and heels
  • Medical device-related pressure ulcers result from the use of devices designed and applied for diagnostic or therapeutic purposes (such as continuous positive airway pressure masks, nasogastric tubes, cervical collars, or splints) [NPIAP, 2016]. Localised forces from the device deform/damage the underlying skin and soft tissues, and the resultant pressure ulcer generally conforms to the pattern or shape of the device. Non-medical devices (such as bed clutter and furniture) can also result in pressure ulcers when they remain in contact with skin and tissues
  • The tolerance of soft tissue for sustained deformations differs by tissue type and may also be affected by age, health status, microclimate, comorbidities, and conditions of the soft tissues. People with conditions that cause inadequate blood flow to the skin and soft tissues (such as peripheral vascular disease, heart failure, diabetes, and sepsis) are at increased risk of developing pressure ulcers

Anyone can get a pressure ulcer, but the following things can make them more likely to form:

  • Marked foot deformity with arthritis / bony prominences, such as the heel bone
  • Being over 70 – older people are more likely to have mobility problems and skin that’s more easily damaged through dehydration and other factors
  • Being confined to bed with illness or after surgery
  • Inability to move some or all of the body (paralysis)
  • Obesity
  • Urinary incontinence and bowel incontinence
  • A poor diet
  • Medical conditions that affect blood supply, make skin more fragile or cause movement problems – such as diabetes, peripheral arterial disease, kidney failure, heart failure, multiple sclerosis (MS) and Parkinson’s disease

Treatment – how to treat pressure ulcers

Adults with pressure ulcers should be assessed and managed by healthcare professionals with the necessary skills and competencies.

Perform a nutritional risk assessment

  • If the person is assessed as being at risk of nutritional deficiency, refer to a dietitian to provide:
    • Advice on how to follow a balanced diet to maintain an adequate nutritional status, taking into account energy, protein, and micronutrient requirements
    • Nutritional supplements (for people with nutritional deficiencies)
  • Do not offer:
    • Nutritional supplements to treat pressure ulcers in adults whose nutritional intake is adequate.
    • Subcutaneous or intravenous fluids to treat pressure ulcers in adults whose hydration status is adequate.

The National Institute for Health and Care Excellence guideline on Nutrition support for adults contains details on nutrition support other than supplements, and advice on energy and protein intake levels.

Consider the need for pressure redistributing devices

  • Recommend high-specification foam mattresses for adults with a pressure ulcer. If this is not sufficient to redistribute pressure, consider the use of a dynamic support surface. A standard-specification foam mattress should not be used for adults with pressure ulcers
  • Consider the seating needs of adults who have pressure ulcers and are sitting for prolonged periods.
  • Consider a high-specification foam or equivalent pressure redistributing cushion for adults who use a wheelchair or sit for prolonged periods and who have pressure ulcers

Assess the need for wound debridement


  • The amount of necrotic tissue
  • The category, size, and extent of the pressure ulcer
  • The person’s tolerance level
  • The impact of the wound on the person’s quality of life (for example odour and exudate)
  • Any comorbidities
  • Risk of infection
  • The skill level of the practitioner

If debridement is indicated:

  • Autolytic debridement should be used, with an appropriate dressing to support it
  • Sharp debridement should be considered if autolytic debridement is likely to take longer and prolong healing time and should only be performed by a trained and competent practitioner
  • Enzymatic debridement should not be routinely offered
  • Larval (maggot) therapy should not be routinely offered. However, it can be considered if sharp debridement is contraindicated or if there is associated vascular insufficiency

Consider the need for antibiotic treatment

  • Offer systemic antibiotics only if there is clinical evidence of systemic sepsis, spreading cellulitis, or underlying osteomyelitis. For more information, see the CKS topic on Cellulitis – acute
  • Discuss with microbiology to ensure that the chosen systemic antibiotic is effective against specific local pathogens
  • Do not offer systemic antibiotics:
    • Specifically, to heal a pressure ulcer.
    • Based only on positive wound cultures, without clinical evidence of infection
  • Do not routinely use topical antiseptics or antimicrobials to treat a pressure ulcer.

Recommend an appropriate wound dressing

  • The choice of dressing should take into account:
    • The person’s pain and tolerance level
    • The position of the ulcer
    • The amount of exudate
    • Frequency of dressing change
  • Consider using a dressing that promotes a warm, moist, wound-healing environment to treat Category 2, 3, and 4 pressure ulcers
  • Do not offer gauze dressings to treat a pressure ulcer
  • For detailed information on wound dressings, see the section on Wound management products and elasticated garments in the British National Formulary (BNF)

Do not

  • Offer electrotherapy or hyperbaric oxygen therapy to treat pressure ulcers
  • Routinely offer negative pressure wound therapy to treat pressure ulcers, unless it is necessary to reduce the number of dressing changes (for example in a wound with a large amount of exudate)

Prevention – how to prevent pressure ulcers occuring

It can be difficult to completely prevent pressure ulcers, but there are some things you or your care team can do to reduce the risk.

These include:

  • Referral to podiatry to assess pressure relief and offloading specifically to the foot
  • Regularly changing your position – if you’re unable to change position yourself, a relative or carer will need to help you
  • Checking your skin every day for early signs and symptoms of pressure ulcers – this will be done by your care team if you’re in a hospital or care home
  • Having a healthy, balanced diet that contains enough protein and a good variety of vitamins and minerals – if you’re concerned about your diet or caring for someone whose diet may be poor, ask your GP or healthcare team for a referral to a dietitian
  • Stopping smoking – smoking makes you more likely to get pressure ulcers because of the damage caused to blood circulation
  • Using specially designed static foam mattresses or cushions, or dynamic mattresses and cushions that have a pump to provide a constant flow of air
  • Relieving/ removing causative pressure such as footwear

If you’re in a hospital or care home, your healthcare team should be aware of the risk of developing heel pressure ulcers. They should carry out a risk assessment, monitor your skin and use preventative measures, such as regular repositioning.

If you’re recovering from illness or surgery at home, or you’re caring for someone confined to bed or a wheelchair, ask your DN / podiatrist for an assessment of the risk of developing heel pressure ulcers.

Other support

Some organisations you can contact for further information.

Accelerate Based in East London, Accelerate can accept national referrals from your GP / specialist to our world-class centre where we pioneer and trial experimental new treatments for chronic leg ulcers / wounds, lymphoedema and mobility challenges.

Contact details
020 3819 6022
Find out more on the Accelerate website

Royal College of Podiatry The Royal College of Podiatry exists to ensure the public has access to high quality foot care delivered by qualified and regulated professionals.

Contact details
020 7234 8620
Find out more on the Royal College of Podiatry website

Diabetes UK Diabetes UK are the leading UK charity for people affected by diabetes it’s their responsibility to lead the fight against the growing crisis. And this fight is one that involves all everyone – sharing knowledge and taking diabetes on together.

Contact details
0345 123 2399
Find out more on the Diabetes UK website

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