A cast is a hard bandage that keeps part of the body from moving so it can heal.
People get casts after a broken bone, some surgeries, and other injuries.
Most casts are made of fiberglass. Fiberglass is a kind of plastic that is moldable and dries hard.
Less often, casts are made of plaster of paris. This white powder is mixed with water into a paste. The paste hardens when it's dried.
Yes, there is a cast that can be worn in showers and pools. A waterproof cast is a regular fiberglass cast with a different type of liner. Doctors use waterproof casts only for some kinds of broken bones.
A health care provider such as an orthopedic surgeon , emergency room doctor, physician assistant , orthopedic technician, or nurse practitioner puts on the cast.
To put on the cast, the health care provider:
A fiberglass cast gets warm as it hardens. It cools in about 15 minutes.
If the cast is not waterproof, keep the cast and liner dry. A wet cast or liner can lead to a skin rash or infection.
Also:
If the cast is itchy:
Casts that don't have a special waterproof liner must be kept dry. It is better to take a bath than a shower because it is easier to keep the cast dry in a bath. To keep the cast dry while bathing:
If the cast or liner gets splashed, gently blow air into it from a hair dryer on the cool or fan-only setting. If some of the cast or liner goes under water or gets very wet, call your doctor.
Health care providers take off casts with a small electrical saw. The saw cuts through the cast material but stops before it touches the skin.
When the cast is off, the skin will probably look pale, dry, or flaky. The hair will look darker and the muscles will look smaller. This is normal and goes away within a few weeks.
Call your doctor if:
Take care of your cast so it stays in good condition and doesn't cause irritation. Within a few months, you can get back to all the activities you enjoyed before the injury.
Reviewed by: Amy W. Anzilotti, MD
Date Reviewed: Mar 1, 2023