What is a cast?
A cast is a hard, protective cover that is wrapped around a broken or fractured bone. A cast holds your injured bone in place while it heals. Once the bone is held still by the cast, it should heal by itself.
A healthcare professional will put your cast on and take it off. While you have a cast, there are important things you should do to care for it.
How is a cast put on?
Casts are always put on by a healthcare professional.
Your healthcare provider will first wrap the injured area in soft cotton or a bandage. Casting material is then dipped in water, before being rolled like a bandage over the padding. The material will harden to form a hard, protective shell. The cast can be made of different materials, such as:
- plaster of Paris
- fibreglass
Your limb (arm or leg) may swell for the first day or so. Sometimes your healthcare provider will make cuts in the full cast or cut it in half lengthwise. These cuts are then secured with tape. This makes sure the cast does not become too tight.
How long will I have a cast for?
The cast usually stays on for 6 weeks. During that time, you’ll need to go back to the hospital or clinic to:
- check the condition of your cast
- see how the bone is healing
Why should I take care of my cast?
After the cast has been put on, you need to look after it. If you don’t look after your cast, it can:
- impact how your injury heals
- make the healing process uncomfortable for you
How do I take care of my cast?
You should follow any cast-care instructions you receive from your healthcare professional.
How do I monitor the fit of my cast?
As your swelling goes down, the fit of your cast may change. Go back to your doctor if your cast is:
- too tight
- rubbing against your skin
Don’t cut or try to change the shape of the cast. Never try to remove a cast yourself.
How do I move around with a cast?
If you have had a plaster cast put on, rest for a couple of days afterwards. Keep the injured limb elevated for the first 2 days. These steps will:
- make sure your cast fully dries
- help stop swelling
- prevent your cast from being too tight
Regularly move your fingers and toes to keep your blood flowing.
If the cast is on your foot, don’t walk directly on it. Use a plaster boot and crutches if you have been given them.
How do I keep my cast clean?
Keep the inside of the cast clean by keeping it away from:
- dirt
- food
- lotions
- sand
A dirty cast can cause infection or irritation. You should not expose the cast to oil.
How do I manage itches?
Don’t put foreign objects inside your cast, such as objects used to scratch the skin. They can cause a rash or infection. Your cast may cause you to feel itchy, but this should go away after a few days.
If you think there is an object inside your cast, contact your doctor.
How do I keep my cast dry?
If your cast is not water resistant, don’t get it wet. When having a bath or a shower:
- put one or 2 plastic bags around the cast
- seal them with a rubber band or duct tape
If you have a water-resistant cast, you may be able to get it wet. Check with your healthcare professional first. Once wet, rinse it with clean water and drain from both ends by changing the position of your cast.
What problems should I watch out for?
Contact your doctor or hospital straight away if you experience:
- a fever
- tingling or numbness in your toes or fingers
- very cold fingers or toes
- swelling in your fingers or toes
- loss of movement in your fingers or toes
- a change in your skin colour to white or blue
- a burning feeling, stinging, pins and needles or persistent pain under your cast
- your cast feeling too tight or too loose
- a bad smell coming from inside your cast
- blisters, a rash, red or raw skin around the edges or inside the cast
Go back to your doctor or hospital within 24 hours if your plaster:
- cracks
- breaks
- goes soft
How is my cast taken off?
Once your bone has healed, the cast is taken off using a special saw. It uses vibrations to break through your cast. This does not hurt or damage your skin.
You should never try to take a cast off yourself.