9 cast questions with Dr. James Engels, chief of pediatric orthopaedics
Casts are never much fun, especially in the summertime. Knowing how to best care for your cast can prevent complications, help the healing process and get you back in action soon!
What’s the purpose of a cast?
A cast holds a broken bone in place and provides comfort by stabilizing your injured body part while it heals. Casts also help prevent or decrease muscle contractions and limit movement, especially after surgery. Sometimes they even make it easier to use an injured extremity while a bone heals.
What are casts made of and how are they applied?
Casts are primarily made up of two layers – an outer hard layer, or shell, and an inner soft padded layer. A thin stocking, or stockinette, goes on directly over the skin. Then we roll on a layer of soft padding before putting on the hard cover. We sometimes apply pressure to the injured extremity to help mold the outer shell. It can be a little uncomfortable momentarily, but is important to help maintain the position of the fracture for healing.
The outer layer is made from one of two types of casting materials:
- Plaster is white in color and gets soft when exposed to water.
- Fiberglass comes in a variety of colors and can withstand some water exposure. With this kind of cast, you can choose what color you want for the outside layer. We have lots of options, and can sometimes even add glitter!
The inner padded layer also can be made from different materials:
- Cotton is most commonly used because of its softness, durability and cost-effectiveness. The downside is that it retains water and can irritate the skin if the cast gets wet.
- Synthetics (polypropylene stockinette, polyethylene padding and/or Gore-Tex) repel water and dry more easily. They can get wet without causing much irritation. Casts with this type of padding are often described as waterproof, but they can only be used for certain injuries. If you’re interested, ask your doctor if a waterproof cast is appropriate for you.
What should I expect after getting a cast?
Mild swelling of an injured area is common during the first few days and may make your cast feel tight initially. To reduce swelling, keep the cast above the level of your heart by resting it on pillows for the first 24 to 48 hours.
Ice can also help keep the swelling down. Apply a bag of ice (or a bag of frozen vegetables) covered with a thin towel to the cast for 20 minutes every 2 hours while awake. Don’t apply ice directly to the skin as it could cause frostbite and other irritation.
Gently move your fingers or toes frequently to limit swelling, prevent stiffness and promote circulation.
It’s important that you also follow all the special instructions given by your healthcare provider to make sure the broken bone heals well.
How should I care for my cast?
- Keep the cast clean and avoid getting dirt or sand inside it. Younger children should have the cast covered when eating.
- Do not apply powder or lotion on or near the cast.
- Do not pull the padding out from inside your cast.
- Do not get the cast wet if it’s plaster and/or lined with cotton padding materials.
What’s the best way to keep my cast dry?
For bathing, place a towel around the top of the cast, cover the cast with a plastic bag, tape the opening shut and hang the cast outside the tub. Even when covered with plastic, you shouldn’t place the cast in water or allow water to run over the area. Commercially available cast covers can be used but still may leak so avoid immersing them as well.
What should I do if my cast gets wet?
If the cast becomes wet, you can dry it with a hair dryer on the cool setting only. The warm or hot setting can burn your skin. You can also use a vacuum cleaner with a hose attachment to pull air through the cast and speed drying. Call the doctor's office to let them know the cast got wet. A plaster cast will likely need to be removed and a new cast applied.
Waterproof casts can get wet with minimal concern for irritation. The padding typically dries on its own within an hour or two, but you can use the cool hair dryer or vacuum approach to speed up the process. After swimming in a pool, rinse the cast with tap water to get rid of chlorine and microorganisms. You still need to avoid rivers, lakes and oceans because sand and debris can get inside the cast and cause problems.
What if I have an itch under my cast?
Do not place anything inside the cast, even for the most annoying itch. Sticking items inside the cast can injure the skin and lead to infection. Using a hair dryer on the cool setting may help soothe itching. Applying synthetic ice packs on the cast can also help alleviate itching, though it may take some time to take effect.
What if the cast has a rough edge that’s causing irritation?
Rough edges can be padded with tape or a Band-Aid to protect the skin from scratches. The band of casting material between the thumb and index finger can be painted with fingernail polish to make it smooth and minimize skin irritation. These may be short term fixes until you can get back to the doctor’s office and we can smooth or replace the cast.
When should I call the doctor if I have concerns about my cast?
It’s important to see a healthcare professional for any of the following:
- Foul odor from the cast
- Cracks or breaks in the cast, or the cast feels too tight/loose
- Swelling that causes pain or makes it so you cannot move your fingers or toes
- Tingling or numbness in the arm, fingers or toes
- Fingers or toes that are blue or cold
- Severe pain in or near the casted arm or leg
- The cast becomes soaking wet and does not dry with a hair dryer or vacuum
While you’re waiting for your bone to heal, see how many signatures you can get on your cast – bonus points for silly sketches!