Cool Cast Facts
Maybe you’ve broken a bone before or you know a kid who has. Kids (and adults) need to wear a cast or splint if they fracture (break) or injure a bone. They’re sometimes used after surgery, too. It isn’t fun to get injured, but it’s important to take care of a cast or splint until it’s time to get it removed.
What Are Casts and Splints?
Casts and splints protect broken and injured bones and help to reduce pain and swelling. They also support soft tissues like muscles and ligaments.
Think of a cast as a big bandage that has two layers. There is a soft cotton layer of padding that rests against the skin and a hard outer layer that prevents the broken bone from moving. The outer layer is usually made of plaster or fiberglass.
Fiberglass casts are made of fiberglass, which is a plastic that can be shaped. Fiberglass casts come in many different colors — if you’re lucky, the doctor may let you pick the color! These casts are lighter and stronger than plaster casts. Plaster casts are usually white and made from plaster of paris, which you may have used for school art projects. Plaster of paris is a heavy white powder. When it’s mixed with water, it forms a thick paste that hardens quickly. Plaster is heavier than fiberglass.
Both materials come in rolls or strips and are cut to fit your injured body part. Some casts are waterproof, but most are not. With a plaster of Paris cast or a fiberglass one, you’ll need to keep it from getting wet. That means using a plastic bag or special sleeve to protect it in the bath or shower.
A splint does the same thing as a cast: It keeps the broken or injured bone from moving so it can heal. It also usually has a soft layer of cotton inside. A splint can be made from the same materials as a cast or may be a pre-made piece of stiff plastic or metal surrounded by strong fabric. It is like a half cast that’s wrapped with an elastic bandage or held in place with Velcro straps. A splint is a good choice for a new injury when there is usually swelling. Like casts, splints should be kept dry. Do not remove your splint unless your doctor says it’s OK.
If you’ve broken your leg and the doctor thinks it is safe, you’ll probably get crutches to help you walk. If the cast or splint is on your arm, the doctor might give you a sling to help support it. A sling is made of cloth and a strap that loops around the back of your neck. It acts like a special sleeve to keep your arm comfortable and in place.
Why Do Kids Need Casts and Splints?
When you break a bone or injure the area around it — whether it’s because you fell off your skateboard or tripped down the stairs — moving the injured area can cause pain. Moving the bone around also can prevent it from healing properly.
Your doctor will want to put the pieces of your broken bone in the right position so they can grow back together into one bone. The cast or splint goes around the injured area to keep the pieces in place. Most kids with broken bones say that their injury feels much better once the cast is on. Depending on the type of injury, you’ll probably have to wear the cast for at least a month.
How Does a Cast or Splint Get Placed?
First, the doctor or cast technician — tech for short (or another person who is trained to put on or take off casts) wraps several layers of soft cotton around the injured area. Next, the plaster or fiberglass outer layer is made wet by putting some water on it. The doctor or cast tech wraps the plaster or fiberglass around the soft first layer. Doctors sometimes make tiny cuts in the sides of a cast to allow room for swelling (puffiness).
When a splint is put on, a layer of cotton goes on first. Next, the splint is placed over the cotton. Then an elastic bandage is wrapped around the splint — or if a pre-made splint is used, straps (which usually have Velcro) keep the splint in place. You and your parent might get instructions on how to do it at home.
The doctor will probably tell you to put the splinted or casted area of your body up for a few days to help reduce swelling. And if you have a “walking cast” on your foot or leg, you shouldn’t walk on it until it’s dry. Fiberglass dries quickly but it will take longer for a plaster cast to be hard enough to use for walking.
Taking Care of Casts and Splints
Keep it dry: Many casts and splints are not waterproof, so keeping it dry is very important. Your doctor may tell you to cover it with a plastic bag while you shower or you can get a special waterproof sleeve to cover it. Depending on where your cast or splint is on your body, you may find it easier to take a sponge bath. This means that instead of getting all wet in the tub or shower, you just use a wet sponge or cloth to clean yourself.
If your cast or splint isn’t waterproof and it gets wet, it may lose its strength and no longer be able to keep the injured bone in place. Once it gets wet, the cotton padding inside the cast is slow to dry. Having a wet cast can cause a rash or infection. If your cast or splint gets wet, tell a parent so your doctor can help.
Keep an eye out for problems: Also tell a parent right away if your cast gets any cracks. This can happen if it’s hit or crushed, has a weak spot, or if the injured area begins to swell underneath. Your parent will call the doctor.
If you notice the cast is causing your fingers or toes to turn white, purple, or blue, tell a parent right away. If it’s too tight, the doctor will want to change it. Also, tell a parent if the skin around the edges of the cast gets red or raw.
Keep yourself comfortable: Even if the skin under the cast or splint gets itchy, don’t put anything inside to scratch the skin. Don’t squirt baby powder, cream, or anything else inside to try to soothe the itch. Try this neat trick instead: Use a blow dryer set on “cool” to blow air inside. It really stops the itch!
Keep it fun: Broken bones aren’t fun, but at least your family and friends can sign your cast. It won’t hurt your cast to have people autograph it. Permanent markers usually work best; washable ones can smear. Feel free to draw pictures on it or decorate your cast with stickers.
How Is a Cast or Splint Removed?
A splint is easy for a doctor or medical technician to remove — the elastic bandage is unwrapped or the Velcro strips detached and the splint is removed quickly.
To remove casts, the outer shell is sawed off. The saw is loud like a vacuum cleaner, but you don’t need to be nervous. This saw’s blade won’t hurt you. The person removing your cast may demonstrate this by letting the saw rub right against his or her skin. The saw has a dull, round blade that vibrates up and down. The vibration is strong enough to break apart the fiberglass or plaster, but it can’t hurt your skin. It may even tickle.
Sometimes your doctor will let you keep your cast or splint as a souvenir — all you have to do is ask. You can look at it in the future, read what your friends wrote on it, and remember how your broken bone got better!
Reviewed by: Steven Dowshen, MD
Date reviewed: January 2014