Education · recovery

Cast and splint care at home Info

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Looking after a plaster or splint at home — keeping it dry, elevation, keeping joints moving, and the urgent signs of a too-tight cast.

A forearm in a cast resting elevated on a pillow at home.
Keeping the arm elevated and the cast clean and dry is the key to a comfortable recovery. Kieran Hirpara 4.0

A cast or splint holds your healing bone, tendon or joint perfectly still so it can mend in the right position. It will be with you for a few weeks, and how you look after it makes a real difference, both to your comfort and to how well things heal. Most of it is common sense, but a few points are worth getting right, and there is a short list of warning signs at the end that you should never ignore.

Keep it clean and dry

This is the single most important rule. A plaster cast that gets wet goes soft and crumbly and stops doing its job. A fibreglass (synthetic) cast holds its shape better, but the soft padding underneath still soaks up water, and damp padding sitting against your skin for hours causes itching, irritation and skin breakdown.

  • Cover it to shower or bathe. Use a proper waterproof cast cover or sleeve, or wrap it in a plastic bag sealed with tape at the top. Even when it's covered, keep the limb out of the direct stream of water and don't dunk it under; a determined splash finds its way in.
  • If covering is awkward, sponge-wash around it instead and keep the cast well clear of the water.
  • If it does get wet, dry the outside and the padding at the edges as best you can with a towel or a hairdryer on the cool setting (never hot; you can't feel a burn through a cast). If a plaster cast gets soaked through, soft, cracked or smelly, call us so it can be checked or replaced.

A removable splint is easier: take it off as we've instructed, keep it dry, and let the skin underneath air and dry fully before you put it back on. Only remove it for the reasons and the length of time we've told you; it's there to protect a healing part.

Never poke anything down inside

The skin under a cast often gets itchy. It's very tempting to slide a knitting needle, pen, ruler or coat hanger down to scratch. Please don't. You can't feel how hard you're scraping, you can break the skin, and a small graze trapped in a warm, dark, padded space is exactly how an infection starts. You can also bunch up the padding and create a pressure point.

If the itch is driving you mad, try tapping the outside of the cast, or blow cool air down it with a hairdryer on the cold setting. Don't put powder, lotion or anything else inside. If the itching is severe or there's a raw, sore spot, tell us rather than battling it yourself.

Don't trim, cut or remove it yourself

It can feel too tight, too long, or just in the way, but never trim, cut, bend or remove a cast or splint on your own. The shape and length are deliberate; cutting it can let the bone shift or leave a sharp edge that digs in. If it genuinely feels too tight or is rubbing badly, that's a reason to contact us, not to take scissors to it (see the warning signs below).

Elevate to settle the swelling

For the first few days, swelling is the main thing working against you, and gravity is the enemy. Keep the limb raised above the level of your heart as much as you can.

  • For an arm or hand, prop it on pillows when you're sitting or lying so the hand sits higher than your elbow, and your elbow higher than your shoulder. A sling helps during the day, but don't let the hand dangle.
  • Raising the limb lets fluid drain back rather than pooling in the fingers, which eases throbbing and stops the cast feeling tighter overnight.

Some swelling and a snug feeling in the first 24–48 hours is normal and settles with elevation. Swelling that keeps getting worse, or that comes with the warning signs below, is not. Get in touch.

Keep moving what you can

A cast stops one part moving, but everything outside it should keep working gently; this prevents stiffness and keeps the blood flowing.

  • Wiggle your fingers and thumb regularly, several times an hour while you're awake, unless we've specifically told you a finger must stay still.
  • Move the joints that are left free: usually your shoulder and elbow if you have a forearm or wrist cast. Gentle shoulder circles and bending the elbow stop those joints seizing up while the wrist heals.
  • Don't force anything that's painful, and follow any specific exercises we've given you.

Protect the cast and the skin

  • Don't bear weight on it or lean on it. It's there to rest the limb, not to take your weight. Leaning on a forearm cast puts pressure on the bone underneath and on your skin.
  • Keep an eye on the skin at the edges. A little redness where the cast meets the skin is common; raw, broken or persistently sore skin is not.
  • Keep the cast clean and avoid dirt, sand or small objects getting inside.

When to seek help — don't wait

Most casts settle down after the first day or two. But a cast that becomes too tight is a genuine emergency: it can squeeze the muscles and nerves inside, cutting off the blood supply (a condition called compartment syndrome), and that can cause permanent damage within hours. The warning signs below are your early alarm. Do not wait.

Contact us the same day, or go to your nearest emergency department, if you notice any of the following:

  • Pain that is increasing, severe, or worse than you'd expect, especially pain that doesn't ease with your usual pain relief, or pain that feels deep and relentless.
  • The cast or splint feeling tighter rather than easier as the days pass.
  • Numbness, pins and needles, or burning in the fingers.
  • Fingers turning pale, white, blue, dusky or cold, or looking very swollen and not settling with elevation.
  • Not being able to move your fingers when you try.
  • A burning, rubbing or pressure spot under the cast: this can be a pressure sore forming.
  • A bad smell coming from the cast, or any discharge or fluid leaking out: a sign of a skin sore or infection underneath.
  • A fever or feeling generally unwell with any of the above.

If you have several of these together, particularly severe pain plus numbness, coldness or colour change in the fingers, treat it as urgent and seek help straight away rather than waiting to see if it settles. It is always better to have a cast checked and find nothing wrong than to leave a tight cast on too long.

For ordinary itching, mild swelling that settles with elevation, or a cast that's simply annoying, you can wait and raise it with us at your next clinic visit. When in doubt, ring the rooms; we would much rather hear from you.