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Arm cast covers: picking the right length and using one with one hand
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- Half arm cast cover for below-elbow casts. Best for: Wrist and forearm casts that stop below the elbow. See options on Amazon
- Full arm cast cover. Best for: Long arm casts that bend the elbow. See options on Amazon
- Hand and wrist cast cover. Best for: Short casts or splints that end at mid forearm. See options on Amazon
- Child arm cast cover. Best for: Children with a forearm or long arm cast. See options on Amazon
Match the cover to the cast
Arm casts come in different lengths, and a cover only works if its seal sits on skin, not on the cast. Use the top edge of your cast to choose.
| Your cast ends | Cover length to look for | Notes |
|---|---|---|
| At the wrist or mid forearm | Hand or short arm cover | Easiest to fit one-handed |
| Just below the elbow | Half arm cover | The cuff should sit on the upper arm, above the elbow crease |
| Above the elbow | Full arm cover | The cuff sits high on the upper arm, so check it does not dig in under the armpit |
Width matters too. A cast with a thumb spica or bulky padding needs a roomier hand section. Measure around the widest part of the cast and around the upper arm where the seal will sit, then compare with the maker's chart.
Why a synthetic arm cast still needs a cover
People often assume a coloured fiberglass cast can get wet. Frimley Health explains that synthetic casts are not damaged by water, but the padding inside takes a long time to dry and the skin underneath can become soggy. AAOS OrthoInfo says damp padding can cause skin irritation. Only casts made with a special waterproof liner are meant to get wet, and your doctor will tell you if you have one.
Getting the cover on with one hand
- Sit at a table and rest the cast on it.
- Open the cuff with your free hand and slide the cover over the fingers first.
- Walk the cuff up the cast a little at a time, rather than pulling once.
- Smooth the seal flat on skin above the cast, with no folds where water can run in.
NHS Lothian's occupational therapy team suggests testing a cover on someone without a cast before you use it, to check it is fully watertight. Even so, keep the arm out of the direct stream: OrthoInfo advises against holding a cast under running water, and warns that a pinhole in a cover can let water reach the injury.
Washing, hair and dressing
- Baths can be easier than showers. KidsHealth suggests resting the covered cast on the side of the tub, out of the water.
- Hair washing. NHS Lothian suggests standing with your back to the sink and tilting your head back, as at a hairdresser, with help if needed.
- Dressing. NHS Lothian suggests stretchy clothes that fit easily over a bulky cast. Put the injured arm in first.
- After washing. Raise the arm to heart level when you sit, as Frimley Health advises, and keep moving the fingers and elbow if they are free.
Plastic bags or a cover?
Advice differs. KidsHealth suggests wrapping a cast in two plastic bags sealed with rubber bands, or using a plastic cast protector. NHS Lothian says plastic bags are not suitable because water can get in. A purpose-made cover with a proper seal is the more reliable choice, but treat any cover as splash protection only.
What to look for when you buy
Half arm cast cover for below-elbow casts
Best for: Wrist and forearm casts that stop below the elbow
Its cuff seals on the upper arm, clear of the top of a below-elbow cast, and the sleeve stays short enough to manage with one hand.
Watch out: Too short for a cast that runs above the elbow.
See options on AmazonFull arm cast cover
Best for: Long arm casts that bend the elbow
The longer sleeve lets the seal sit high on the upper arm, above the top edge of an above-elbow cast.
Watch out: Harder to put on alone; ask someone to help settle the seal the first few times.
See options on AmazonHand and wrist cast cover
Best for: Short casts or splints that end at mid forearm
A short cover is quick to fit with one hand and leaves the elbow free to move, which Frimley Health encourages when the cast allows.
Watch out: Check it fits over a thumb spica or bulky hand section.
See options on AmazonChild arm cast cover
Best for: Children with a forearm or long arm cast
A small limb leaks through an adult cuff. KidsHealth notes that some families use a waterproof plastic cast protector instead of plastic bags.
Watch out: Keep the cast out of the bath water even when covered.
See options on AmazonQuestions people ask
- Can I shower with an arm cast cover?
- Yes, for splashes. Keep the covered arm out of the direct stream, since OrthoInfo advises against holding a cast under running water.
- Do fiberglass arm casts need a cover?
- Usually yes. Frimley Health says synthetic casts are not damaged by water, but the padding stays wet for a long time and the skin can become soggy.
- What size arm cast cover do I need?
- Pick a length that ends on bare skin above your cast, then check the maker's chart against the widest part of the cast and your upper arm.
- How do I check a cast cover does not leak?
- NHS Lothian suggests testing it on someone without a cast first. Also look for pinholes before each use.
- What if my arm cast gets wet anyway?
- Contact your plaster room or doctor. KidsHealth advises calling your doctor if the cast goes under water or gets very wet.
Sources
- Instructions and advice about your plaster cast: upper limb (fhft.nhs.uk), Frimley Health NHS Foundation Trust
- Care of Casts and Splints (orthoinfo.org), AAOS OrthoInfo
- Occupational therapy advice for people in a cast (policyonline.nhslothian.scot), NHS Lothian
- Casts (kidshealth.org), Nemours KidsHealth