What is a cast?

By Steve Cutler, OTC

Casts have been used to treat broken bones since the time of the pharaohs of ancient Egypt. Plaster of Paris has been used for casts since the 1800’s and only recently have synthetic materials such as fiberglass and polyester been used.

Casts are designed to immobilize (keep still) a broken bone or an injured joint. This “stillness” allows the natural healing of the body to make the patient better. The idea is to make the patient as good as they were before the injury.

Plaster is the traditional white, hard as a rock substance that is generally thought of as a cast. It molds very well and has stood the test of time. However, it has limitations. It is heavy, not very durable and will fall apart if exposed to water. Since treating methodologies have evolved over the years, your doctor tries to get you back to work or school as soon as possible. This is where synthetics enter the scene.

Most synthetic casts used today are made from fiberglass, the same material used to make NASCAR racing car bodies. The fiberglass is woven like a cloth and covered with a sticky substance called polyurethane. The sticky substance, when dipped in water, will harden and form a cast. The fiberglass cast is lighter and stronger than plaster. When exposed to water it will not fall apart. In a sense, each cast is custom made to properly fit the individual patient and is padded with a soft synthetic cotton-like substance. This makes the cast comfortable and protects the skin from abrasions that can be caused by the hard cast.

Your doctor will decide what kind of cast to apply and what type of material to use according to your particular injury. The cast is left on until there is sufficient healing at which time a cast saw is used to remove it. A cast saw is an electric saw with a sharp blade that only oscillates (moves back and forth) and doesn’t spin. It makes a loud noise but won’t hurt you.

If you have any questions concerning your cast, please call our office and talk to one of your ortho techs. They will try to answer any questions concerning your cast. If need be they will make an appointment to be seen.