Pressure ulcers in multiple sclerosis: how they form, how to prevent them and how to treat them

2 September 2026

A pressure sore can develop in a few hours and take months to heal. Here is why the risk is higher in MS than in most conditions, what the stages look like, which prevention measures actually work (offloading, cushions, skin care, nutrition) and how modern wound care treats each stage.

A friend from our association showed me a coin-sized sore over his sitting bone a few years ago. It appeared over a single weekend — a new chair, a long drive, and he simply did not shift position. It took eleven months to close.

That is the single most important thing to know about pressure ulcers: the asymmetry. A few hours of immobility produce a wound that then eats a year of your life, with the risk of bone infection and hospitalisation along the way. That is why this article is more about prevention than about treatment.

Why the risk is higher in MS

A pressure ulcer forms when pressure on skin and tissue over a bony prominence cuts off the blood supply. Tissue deprived of oxygen starts to die, and it does so from the inside out — next to the bone first — which is why the damage on the surface often underestimates what is underneath.

In multiple sclerosis it is rarely one factor; it is several arriving together. Reduced mobility means longer sitting or lying in the same position. Sensory loss means the brain never receives that uncomfortable "move now" message a healthy person gets every few minutes — without the person noticing anything. Spasticity and spasms drag the body into slanted postures and create shear, the sideways force that tears tissue and is far more dangerous than pure pressure. Bladder and bowel problems mean damp skin, and damp skin breaks down at a fraction of the load. Fatigue and depression reduce the will to reposition and to inspect the skin. Poor nutrition and low protein intake slow every repair process.

If several of these apply at once — and most people with an EDSS above 6 have them — the risk is not theoretical.

> If you use a wheelchair or spend most of the day in one chair, ask your doctor or physiatrist for a Braden scale risk assessment. It is a standard six-item questionnaire (sensory perception, moisture, activity, mobility, nutrition, friction and shear) and takes five minutes.

Where ulcers form

Ulcers do not appear just anywhere; they appear exactly over bone. In people who sit: the sitting bones (ischial tuberosities), the tailbone, the outer hip. In people who lie down: the sacrum, heels, shoulder blades, elbows, back of the head, and the inner knees where the legs touch. Heels are treacherous because nobody looks at them — and the heel has thin skin with almost no muscle underneath.

The stages — and why stage 1 is not harmless

The international classification (EPUAP/NPIAP) has four stages plus two extra categories:

- Stage 1: skin intact but reddened, and the redness does not fade when you press it with a finger. On darker skin it shows as a colour change, warmth or firmness. - Stage 2: loss of the surface layer — a shallow open sore or a blister. - Stage 3: the wound goes through the full thickness of skin into the fatty tissue beneath. - Stage 4: muscle, tendon or bone is visible. - Unstageable: the wound bed is covered in slough or eschar so depth cannot be assessed. - Deep tissue injury: a purple or maroon patch under intact skin — the damage is already down at the bone.

Stage 1 is the only stage that reverses on its own, and only if pressure is removed completely. Redness that does not blanch when you press it is not irritation — it is the beginning of a wound and demands offloading of that spot immediately, not tomorrow.

Prevention — what actually works

Offloading is the one measure without a substitute. If you sit, do a pressure relief every 15 to 30 minutes: lean forward, lean to the side, or push up on your arms if you have the strength — each time for at least 30 seconds, because blood needs time to return. Tilt-in-space wheelchairs do this for you, provided the tilt is at least 30 degrees and held for a minute or two.

If you lie down, change position roughly every two hours, using a 30-degree side-lying position rather than a full side turn — full side-lying loads everything onto the hip bone. A pillow between the knees, and heels floated completely off the mattress on a pillow under the calves. Never use ring cushions or "donuts": they cut circulation around the rim and create a ring-shaped wound.

The surface you sit and lie on is the other half of the job. A viscoelastic foam or air-cell cushion for the wheelchair, and a pressure-redistributing mattress if much of the day is spent in bed. A cushion is not for life — foam compresses within a year or two and then stops working. Press it: if you can feel the base under your sitting bone, it is time for a new one.

Inspect the skin every day. Morning or evening, always at the same time, using a hand mirror for the areas you cannot see, or have a family member check. You are looking for redness that does not fade, colour change, firmness, warmth. Wash with lukewarm water and a mild cleanser, dry by patting rather than rubbing, and use a barrier cream if there is incontinence. Never massage a reddened area — massage over already damaged tissue adds injury.

Nutrition is the forgotten part. Healing needs more protein than usual, roughly 1.25 to 1.5 g per kilogram of body weight per day, with enough fluids, vitamin C and zinc. Someone who eats little because of fatigue or swallowing problems will not close a wound however good the dressings are. If swallowing is an issue, more here: [swallowing and speech problems in MS](/en/blog/swallowing-and-speech-problems-ms-speech-therapy-exercises).

Spasticity is worth treating for the skin's sake too, not just for comfort — a spasm that pushes you into the same position every night is a mechanical cause of wounds. More on that: [spasticity and spasms in MS](/en/blog/ms-spasticity-muscle-spasms-complete-guide-causes-medication-exercises). The same goes for the bladder: damp skin is weak skin, so [sorting out urinary problems](/en/blog/water-retention-and-urinary-retention-in-multiple-sclerosis) is part of pressure ulcer prevention.

Treatment by stage

The first rule is identical for every stage: a wound does not heal while pressure remains on it. Everything else is secondary. If the sore sits over an ischial bone, sitting on that spot must be cut to a minimum, however impractical that is.

In stage 1, complete offloading, skin protection and daily monitoring are enough. The redness usually recedes within days.

In stage 2, the wound is cleaned with saline — not hydrogen peroxide or iodine, which damage new cells — and covered with a dressing that keeps a moist environment: hydrocolloid, polyurethane foam or film. A moist wound heals faster than a dry scab; that is now the standard.

In stages 3 and 4, professional care is required. Dead tissue must be removed (surgically, enzymatically or by autolytic dressings), and the wound is filled according to how much it weeps — alginate and hydrofiber for heavy exudate, foam for moderate. Negative pressure wound therapy (NPWT, the "vacuum") speeds up closure of deep wounds. Deep sores over the sitting bones sometimes need flap reconstruction, done by a plastic surgeon.

Antibiotics are not given routinely. Every open wound harbours bacteria; that is not an infection. Antibiotics belong to true infection: spreading redness around the wound, pus, foul odour, worsening pain, fever, or a wound that deteriorates despite good care. If bone is visible or can be probed at the wound base, osteomyelitis must be ruled out.

When to call a doctor the same day

- redness that does not blanch and does not recede within 24–48 hours of offloading - any wound deeper than the surface layer of skin - a purple or dark patch under intact skin - fever, pus, foul odour or suddenly worse pain - a wound that has not shrunk after two weeks of correct care

Do not wait for your routine neurology appointment. A pressure ulcer is handled by a surgeon, a community nurse or a wound clinic, and time is the one resource you cannot get back.

For me personally, the thing that finally worked was a stupidly simple one: a phone alarm every 30 minutes while I sit at my desk. The first week it was irritating; after that it became a habit and the alarm was no longer needed.

This article is educational and does not replace examination and advice from a doctor.