Cast Care

ExitCare ImageThe purpose of a cast is to protect and immobilize an injured part of the body. This may be necessary after fractures, surgery, or other injuries. Splints are another form of immobilization; however, they are usually not as rigid as a cast, which accommodates swelling of the injury while still maintaining immobilization. Splints are typically used in the immediate post injury or postoperative period, before changing to a cast.

Before the rigid material of a cast is formed, a layer of padding is first applied to protect the injury. The rigid portion of a cast is created by wrapping gauze saturated with plaster of paris around the injury; alternatively, the cast may be made of fiberglass. During the period of immobilization, a cast may need to be changed multiple times. The length of immobilization is dependant on the severity of the injury and the time needed for healing. This period can vary from a couple weeks to many months.

After a cast is created radiographs (x-rays) through the cast determine if a satisfactory alignment of the bones was achieved. Radiographs may also be used throughout the healing period to check for signs of bone healing.


  • Allow the cast to dry and harden completely before applying any pressure to it.

  • Applying pressure too early may create a point of excessive pressure on the skin, which may increase the risk of forming an ulcer. Drying time depends on the type of cast, but may last as long as 24 hours.

  • When a cast gets wet, a soft area may appear. If this happens accidentally, return to the doctor's office, emergency room, or outpatient surgical facility as soon as possible for repairs or changing of the cast.

  • Do not get sand in the cast.

  • Do not place anything inside the cast, this includes items intended to scratch an area of skin that itches.


  • It is very common for a person with a cast to experience an itching sensation under the cast.

  • Do not scratch any area under the cast even if the area is within reach. The skin under a cast in an environment of increased risk for injury.

  • Do not put anything in the cast.

  • If there is no wound, such as an incision from surgery, you may sprinkle cornstarch into the cast to relieve itching.

  • If a wound is present under the cast, consult your caregiver for pain medication or medication to reduce itching.

  • Using a hairdryer (on the cold setting) is a useful technique for reducing an itching sensation.


It is important to elevate the body part that is in a cast to a level equal to or above that of the heart whenever possible. Elevating the injured body part may reduce the likelihood of swelling. Elevation of a leg in a cast may be achieved by resting the leg on a pillow when in bed and on a footstool or chair when sitting. For an arm in a cast, rest the arm on a pillow placed on the chest.

No matter how well one follows the necessary precautions, excessive swelling may occur under the cast. Signs and symptoms of excessive swelling include:

  • Severe and persistent pain.

  • Change in color of the tissues beyond the end of the cast, such as a change to blue or gray under the nails of the fingers or toes.

  • Coldness of the tissues beyond the cast when the rest of the body is warm.

  • Numbness or complete loss of feeling in the skin beyond the cast.

  • Feeling of tightness under the cast after it dries.

  • Swelling of the tissue to a greater extent than was present before the cast was applied.

  • For a leg cast, inability to raise the big toe.

If any of these signs or symptoms occur, contact your caregiver or an emergency room as soon as possible for treatment.

Infection Inside a Cast

On occasion, and injury may become infected during healing. The most important way to fight an infection is to detect it early, however, early detection may be difficult if the infected area is covered by a cast. Infection should be reported immediately to your caregiver. The following are common signs and symptoms of infection:

  • Foul smell.

  • Fever greater than 101° F (38.3° C) (may be accompanied by a general ill feeling)

  • Leakage of fluid through the cast.

  • Increasing pain or soreness of the skin under the cast.

Bathing with a Cast

Bathing is often a difficult task with a cast. The cast must be kept dry at all times, unless otherwise specified by your caregiver. If the cast is on a limb, such as your arm or leg, it is often easier to take a bath with the extremity in a cast propped up on the side of the tub or a chair, out of the water. If the cast is on the trunk of the body, you should take sponge baths until the cast is removed.