Cast care: Do's and don'ts

Wondering about cast care? Get the answers to common cast care questions, from keeping a cast clean and reducing swelling to knowing when to call the doctor. By Mayo Clinic Staff

If your child breaks a bone, a cast can help support and protect the injury as it heals. Without proper care, however, a cast can't do its job. Understand the basics of cast care and how a cast can promote your child's recovery.

What are the different types of casts?

Casts are custom-made to fit and support injured limbs. There are two main types of casts:

  • Fiberglass casts. Fiberglass is a type of plastic that can be shaped. Fiberglass casts are typically lighter and more durable than traditional plaster casts. Air circulates more freely inside a fiberglass cast. Also, X-rays penetrate fiberglass casts better than plaster casts. This is helpful if your child's doctor wants to use an X-ray to examine your child's bones while he or she is still wearing the cast. Fiberglass casts are available in different colors.
  • Plaster casts. Plaster casts are easier to mold for some uses than are fiberglass casts. Also, plaster casts are typically less expensive than fiberglass casts.

What can be done to reduce swelling?

Swelling can cause your child's cast to feel tight and uncomfortable. To reduce swelling:

  • Elevate the affected area. For the first 24 to 72 hours after your child's cast is applied, use pillows to raise the cast above the level of your child's heart. If possible, try to keep the cast raised even while your child is asleep.
  • Keep moving. Encourage your child to frequently move the fingers or toes of his or her injured limb.
  • Apply ice. For the first 48 to 72 hours after your child's cast is applied, loosely wrap an ice pack covered in a thin towel around your child's cast. Apply ice to the cast — not the skin — for 20 minutes every two hours. If your child is asleep, there's no need to wake him or her to apply the ice.

What can I do if my child wants to scratch under the cast?

A cast can cause your child's underlying skin to feel itchy. To relieve itchy skin:

  • Set a hair dryer on a cool setting and aim it under the cast
  • Apply an ice pack covered in a thin towel to the area
  • Ask your child's doctor about giving your child an over-the-counter antihistamine

Don't allow your child to stick objects, such as a coat hanger, inside the cast to scratch his or her skin. This could injure your child's skin and cause an infection.

Apr. 28, 2012 See more In-depth