About Cast and Splints

Splints and casts support and protect injured bones and soft tissue, reducing pain, swelling, and muscle spasm. In some cases, splints and casts are applied following surgery.

Casts

Casts are custom-made and applied by your doctor or an assistant. Casts can be made of plaster or fiberglass which form the hard supportive layer. Fiberglass is lighter in weight, longer wearing, and "breathes" better than plaster. Plaster is less expensive than fiberglass and, shapes better than fiberglass for some uses. Both materials come in strips or rolls, which are dipped in water and applied over a layer of cotton or synthetic padding covering the injured area. X-rays to check the healing process of an arm or leg within a splint or cast penetrate or "see through" fiberglass better than plaster.

Splints

Splints or "half-casts" provide less support than casts. However, splints can be adjusted to accommodate swelling from injuries easier than enclosed casts. Splints or half-casts also can be custom-made, especially if an exact fit is necessary. Other times, a ready-made splint will be used. These off-the-shelf splints are made in a variety of shapes and sizes, and are much easier and faster to use. They have Velcro straps, which make the splints easy to adjust, and to put on and take off. Your doctor will explain both how to use your injured arm or leg while it is healing and how to adjust your splint to accommodate swelling.

Application

Your doctor will decide which type of support will be best for you.

Both fiberglass and plaster splints and casts use padding, usually cotton, as a protective layer next to the skin. The splint or cast must fit the shape of the injured arm or leg correctly to provide the best possible support. Generally, the splint or cast also covers the joint above and below the fractured bone. Frequently, a splint is applied to a fresh injury first and, as swelling subsides, a full cast may be used to replace the splint. Sometimes, it may be necessary to replace a cast as swelling decreases and the cast "gets too big." Often as a fracture heals, a splint may be applied again to allow easy removal for therapy.