Casts and Splints
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Casts and Splints

What are casts and splints?

Casts and splints are hard wraps used to support and protect injured bones, ligaments, tendons and other tissues. They help broken bones heal by keeping the broken ends together and as straight as possible. Casts and splints also help relieve pain and swelling, and protect the injured area from more harm.

What is the difference between a cast and a splint?

All casts are custom-made with fiberglass or plaster. A cast wraps all the way around an injury and can only be removed in the doctor’s office.

A splint is like a half cast. The hard part of a splint does not wrap all the way around the injured area like it does with a cast. Instead, there are usually 2 hard areas connected with an elastic bandage or other material that hold the splint in place. Unlike casts, splints can be easily removed or adjusted. Splints can be custom-made from fiberglass or plaster, or may be ready-made. Splints come in lots of shapes and sizes for different injuries.

How long does a cast or splint stay on?

A splint usually stays on for several days to a few weeks. If your injured area is very swollen, you may need a splint until the swelling goes down. You may still need a cast after the swelling goes down. Also, if your injury is swollen, both splints and casts may need to be adjusted in the first few days. As the swelling goes down, a cast or splint may become too loose. If swelling increases, the splint or cast may become too tight.

Casts that are kept in good condition can stay on for several weeks. Your doctor will tell you how long your cast will need to stay on.

What if the pain gets worse?

Some people have mild pain and swelling if they don’t rest the injured area enough. To avoid this, it is important to remember the following:

  • Keep the injured area above the level of your heart (for instance, prop it up with pillows).
  • Wiggle your fingers or toes while resting.
  • Apply ice, if needed. Ice can be used for 15 to 30 minutes over a cast or splint as long as it doesn’t get the splint or cast wet or touch the skin for too long.
  • Talk to your doctor before taking pain medicine.

When should I call my doctor?

Call your doctor right away if you have:

Your doctor may need to adjust, remove or change your splint or cast.

  • Increased pain
  • Numbness, tingling, burning or stinging on or near the injured area
  • Circulation problems (if your skin, nails, fingers or toes become discolored, pale, blue, gray or cold to the touch, or if you have trouble moving your fingers or toes)
  • Bleeding, pus, drainage or bad smells coming from the cast
  • A wet, broken or damaged cast or splint

Can I bathe or shower if I have a cast or splint?

Yes. But be sure to keep your cast or splint dry, especially during baths and showers. Casts and splints made from plaster can break if they get wet. Fiberglass casts are water-resistant, but the lining will absorb water. And if moisture gets trapped in the cast or splint, it can irritate your skin or cause an infection.

When you bathe or shower, wrap 2 layers of plastic over the cast or splint and make sure a plastic bag is tightly sealed over it. This will make it water-resistant, but not waterproof, so do not put the cast or splint directly in water.

What else do I need to know if I have a cast or splint?

Take good care of your cast or splint to help your injury heal properly. Also remember:

  • Never stick objects inside a cast or splint. They can get stuck, break off or damage your skin.
  • Don’t get dirt or sand inside a cast or splint.
  • Don’t apply powders or deodorants inside a cast. If you have severe itching, call your doctor.
  • Never break off pieces of your cast or splint or try to adjust it yourself. If it needs to be adjusted, call your doctor.
  • Check the cast and the exposed skin daily. If you notice damage to the cast or any injury, call your doctor.

How is a cast taken off?

Your doctor will use a special cast saw with a blade that vibrates but does not spin. It cuts through the outer layer, but not the lining.

Never remove a cast yourself. Using any type of home saw or cutting materials could cause serious injury to your skin, blood vessels and injured limb.

Other Organizations


  • Principles of Casting and Splinting by Anne S. Boyd, MD, Holly J. Benjamin, MD, and Chad Asplund, MAJ, MC, USA( 01/01/09,