Cushions for Wheelchair Users: Skin and Posture

What a wheelchair cushion needs to do

• Protect the skin. Reduce pressure over the sit bones, tailbone and hips, and lower shear and moisture.
• Support the posture. Keep the pelvis level and the thighs and hips well positioned, which helps the whole spine, shoulders and head.
• Be stable. A cushion that slides or tilts causes problems.
• Fit the chair and the person. Size and thickness matter.
• Be easy to care for. Washable covers, durable materials.

For the background to pressure damage and routines, see pressure care in a wheelchair.

Assess the risk first

Cushion choice depends on how likely the person is to develop a pressure sore. Higher risk applies to people who:

• sit in the chair for most of the day;
• cannot shift their own weight;
• have reduced feeling, such as after stroke or with neuropathy;
• are very thin, frail or underweight, or very heavy;
• have had a pressure sore before;
• have diabetes, poor circulation or poor nutrition;
• have incontinence, so that skin is damp; or
• have fragile skin.

Low-risk people, who sit for short periods and can move easily, may manage with a good foam cushion. Medium-risk people usually need a gel or high-quality contoured foam cushion. High-risk people need a specialist air, fluid or combination cushion, chosen by a therapist.

Main cushion types

### Foam

High-density foam, flat or contoured. Light, inexpensive and easy to look after. Quality varies, and cheap foam flattens within months. Suitable for low risk and short periods.

### Contoured foam

Shaped to fit the buttocks and thighs, spreading load and giving positional stability. Good for medium risk and posture support. Needs to be placed the right way round.

### Gel and gel-foam

A gel layer on foam, spreading pressure and keeping cooler. Heavier but popular for medium risk. See gel cushions for pressure relief.

### Air-filled cushions

Cells of air, often connected, that adjust to the body. Excellent pressure relief for higher-risk people when properly inflated, but need regular checking, can puncture and may feel unstable for some people.

### Fluid and combination cushions

Fluid-filled sections and foam or gel and air combined. Used for very high risk or complex posture needs.

### Alternating pressure and powered cushions

Rarely used at home; motorised cells that change pressure regularly. Specialist.

### Ring and donut cushions

Not recommended for pressure relief; see ring and donut cushions.

Posture and position

A cushion also shapes how the person sits.

• Pelvic tilt. A cushion that tilts the pelvis backward causes slouching; forward, an upright posture. Therapists adjust with wedges and contours.
• Lateral support. Side supports or contouring help those who lean to one side.
• Thigh support. The cushion should support the thighs and stop the legs falling outwards.
• Hips level. Uneven cushions twist the spine.
• Sliding. A cushion with a non-slip base and a contoured front lip reduces sliding forward.

Poor posture affects breathing, swallowing, eating and shoulder comfort, as well as skin. If your parent slumps or leans, ask a therapist about a posture cushion or a supportive backrest.

Fit and size

A cushion should match the chair seat and the person.

• Width. About the same as the seat, or slightly narrower. Too wide a cushion bunches or hangs; too narrow leaves gaps.
• Depth. A little shorter than the seat, leaving about 2.5 to 5 cm clear behind the knee.
• Thickness. Typically 5 to 10 cm. A thicker cushion raises the seat, so check armrest, footrest and table height; see wheelchair measurements.
• Weight limit. Check that it exceeds the user's weight.
• Seat base. A flat, firm base is better than a sagging sling. A rigid seat board under the cushion helps.

Checking the cushion works

1. Place it correctly, right side up, front to front, on a firm base. 2. Sit well back, with hips against the backrest. 3. Slide a flat hand under the sit bones. You should feel cushion material, not the hard seat. If you feel the base, the cushion is bottoming out. 4. Check posture: pelvis level, thighs supported, feet on footplates. 5. Check comfort after 10 to 15 minutes. 6. Look at the skin after a few hours: any redness that does not fade in 30 minutes needs attention.

For air cushions, check the inflation as per the instructions, usually by the hand-check method.

Covers, moisture and heat

• Breathable covers with a two-way stretch help prevent heat and sweat.
• Waterproof covers protect the cushion from incontinence but can trap moisture; choose breathable waterproof fabrics and change promptly. See incontinence-associated skin damage.
• Wash covers regularly as instructed.
• Avoid sitting directly on plastic.
• In hot Indian summers, gel and breathable materials keep cooler; avoid thick memory foam.

Care and replacement

• Check the cushion weekly for lumps, flat areas, leaks or damage.
• Clean the surface and cover; air the cushion.
• Do not use sharp objects near air or gel cushions.
• Replace when worn: foam can flatten in six to twelve months; gel and air last longer with care.
• Keep a spare cover.
• Do not share cushions between users.

See cushion covers, washing and hygiene.

Cushions in rented or borrowed chairs

Rented and hospital wheelchairs usually have thin seats. If your parent will be in the chair for more than a few hours, bring or buy a suitable cushion. It is personal and hygienic. See renting or buying a wheelchair.

Transit chairs and outings

For short outings in a transit chair, a lightweight foam or gel cushion is often enough, but remember that even short trips add up for people at high risk. Take a cushion with you for car journeys and clinic visits. See transit wheelchair or standard wheelchair.

Other equipment for sitting

• Back support. A supportive backrest or lumbar cushion; see lumbar cushions.
• Footrests and leg supports at the right height.
• A seat belt or pelvic strap, if sliding is a problem.
• Lateral supports, head supports and arm troughs, prescribed by therapists.
• A tilt-in-space or reclining chair for those who cannot shift weight.
• A bed with a pressure-relieving mattress for the rest of the day; see air mattress for pressure sores.

Questions to ask a supplier or therapist

• What level of pressure risk is this cushion designed for?
• What is the weight range?
• How do I check it is working?
• How do I clean it, and how long will it last?
• What is the warranty?
• Can I try it first?
• Does it suit my parent's chair and posture?
• What happens if it is damaged?

When to ask a professional

An occupational therapist or seating specialist can assess risk and posture, trial cushions and teach checks. Ask for an assessment if your parent sits for many hours, has had a pressure sore, has posture problems or uses a wheelchair full time. See a nurse or doctor at once for any skin that is red, blistered, broken or painful. Our care advisors can arrange a nurse visit and recommend cushions.