In a plaster? Home care and the warning signs not to ignore

First things first

A note on the evidence

A cast (plaster or fibreglass) holds a broken bone or injured joint still while it heals. No trials have tested home cast-care advice such as raising the limb, keeping it dry or managing itching. The advice here comes from an NHS hospital leaflet and expert opinion ^[1]. Your own doctor’s instructions come first.

The first few days

Keep the swelling down

• Keep the limb raised as much as you can, especially in the first few days ^[1].
• Arm in a cast: keep your hand at or above the level of your heart ^[1].
• Leg in a cast: rest it on pillows so it is higher than your hip, without pressure on the heel ^[1].
• Keep moving the fingers, toes and any joints that are not in the cast ^[1].

Day to day

Keep it dry, and leave the inside alone

• Keep the cast dry. A wet cast can make the skin underneath break down and raises the risk of infection ^[1]. There is no research on Indian heat, sweat or bathing at home, so ask your clinic how to bathe safely with your cast.
• Itching: never push anything inside the cast to scratch. It can damage the skin and cause infection ^[1].
• Pressure sores: a burning or blister-like pain, or soreness under the cast, is a warning sign. So are rubbing, a bad smell or discharge ^[1].

Rare but serious

Compartment syndrome

This is a rare emergency in which pressure builds up inside the muscles and can cut off their blood supply. It can start when a cast or bandage is too tight ^[2].

• The main signs: pain that is far worse than you would expect from the injury, and pain that gets worse when someone gently moves your fingers or toes for you (this stretches the muscles) ^[3].
• Other signs: swelling, tightness, numbness, pins and needles, weakness, and difficulty moving the fingers or toes ^[2].

No single sign is reliable on its own, which is why doctors need to examine the limb ^[4]. If it is missed, compartment syndrome can cause permanent nerve damage, stiff, bent joints that can’t straighten (contractures), and even loss of the limb ^[5]. Sudden severe pain needs emergency care ^[2].

Leg in a cast

Blood clots

If your leg is in a plaster, watch for signs of a blood clot. A DVT (deep vein thrombosis) is a clot in a leg vein; a PE (pulmonary embolism) is a clot that travels to the lungs. Watch for pain or swelling in the calf, and for chest pain or breathlessness ^[6]. In a large trial of people in a lower-leg cast, routine blood-thinning injections did not prevent clots that caused symptoms (1.4% with injections, 1.8% without) ^[7]. UK NICE guidance says injections may be considered when a person’s clot risk outweighs their bleeding risk ^[8]. Your doctor will decide whether you need them.

Children

If your child is in a plaster

Children may not describe what they feel clearly, so parents and carers should watch for the same warning signs listed below (expert advice).

Talking it through

Questions to ask before you leave

• How long will the cast stay on, and when is my next check?
• How should I bathe, and how do I keep the cast dry?
• Do I need blood-thinning injections?
• Where do I go if a warning sign appears at night?

Dr Aditya Aggarwal treats fractures and injuries at Aggarwal Clinic, Patiala. For any warning sign above, go to the nearest emergency department rather than sending a message.

Sources

References

1. Kingston and Richmond NHS Foundation Trust. Caring for your cast (patient leaflet). Kingston and Richmond NHS FT; updated 2025. kingstonandrichmond.nhs.uk/patients-and-families/patient-leaflets/caring-your-cast
2. NHS. Compartment syndrome. NHS website; reviewed 4 Sep 2026. nhs.uk/conditions/compartment-syndrome
3. British Orthopaedic Association. BOA Standard (BOAST): diagnosis and management of compartment syndrome of the extremities. BOA; revised 2025. boa.ac.uk
4. Lorange JP, et al. Diagnosis accuracy for compartment syndrome: a systematic review and meta-analysis. J Orthop Trauma. 2023;37(8):e319-e325. doi:10.1097/BOT.0000000000002610
5. von Keudell AG, et al. Diagnosis and treatment of acute extremity compartment syndrome. Lancet. 2015;386(10000):1299-1310. doi:10.1016/S0140-6736(15)00277-9
6. NHS. DVT (deep vein thrombosis). NHS website; reviewed 30 Apr 2026. nhs.uk/conditions/deep-vein-thrombosis-dvt
7. van Adrichem RA, et al. Thromboprophylaxis after knee arthroscopy and lower-leg casting. N Engl J Med. 2017;376(6):515-525. doi:10.1056/NEJMoa1613303
8. National Institute for Health and Care Excellence. Venous thromboembolism in over 16s: reducing the risk of hospital-acquired deep vein thrombosis or pulmonary embolism (NG89). NICE; 2018, updated 2019. nice.org.uk/guidance/ng89

Evidence checked 5 October 2026.

Next step

WhatsApp your reports to +91 84477 30708, or call +91 98768 24676, to arrange a consultation with Dr Aditya Aggarwal at Aggarwal Clinic, Patiala. No diagnosis or treatment advice is given over WhatsApp.