Orthopedic Center
Cast care and maintenance
A cast holds a broken bone in place as it heals. Casts also help to prevent or decrease muscle contractions, are helpful at providing immobilization, especially after surgery, and therefore can help decrease pain. Casts immobilize the joints above and below that area that is to be straight and without motion. For example, a child with a forearm fracture will have a long arm cast to immobilize the wrist and elbow joints.
What are casts made of?

The outside, or hard part of the cast, is made from two different kinds of materials: plaster and fiberglass. Cotton and other synthetic materials are used to line the inside of the cast to make it soft and provide padding around bony areas, such as the wrist or elbow. They also pad nerves and blood vessels from pressure (see image on right for examples of padding materials: (l) gortex, (r) cotton).
Special waterproof cast liners may be used under a fiberglass cast, allowing the child to get the cast wet. These waterproof liners can only be used when the swelling from the injury has decreased, usually a week or two after fracture. They can’t be used after surgery or when pins are used due to a risk of infection.
| Material | Benefits |
|---|---|
| Plaster |
|
| Fiberglass |
|