What is a total contact cast?
A total contact cast is a cast used to treat ulcers (serious, deep sores) on a person’s foot. It consists of a fiberglass shell that fits around your leg and foot very closely and has a bar on the bottom. The shell touches your whole foot--that's why it is called a total contact cast.
The cast helps to protect the skin on your foot. Where the cast sits under the ulcer, there is a layer of soft foam. This makes a space so that no pressure is put on the sore and it can heal more quickly. The cast has only a small amount of padding around the rest of the foot. The bar on the bottom keeps weight off of your foot when you are standing or walking.
Why do I need a cast?
People who have diabetes often have trouble with their feet. Part of the problem is that the loss of feeling in your feet makes it hard for you to tell if you have a blister or sore. If little sores aren't taken care of, they can get worse and turn into ulcers.
The total contact cast will help your ulcer heal. If you keep walking without the cast, the ulcer won't heal. The cast takes pressure off the ulcer.
Wearing a total contact cast helps most ulcers heal in 6 to 8 weeks. Your doctor will probably change your cast 1 to 2 days after it is put on. After that, you'll probably get a new cast every week until you are ready to wear shoes.
What do I need to know about my cast?
Depending on the type of cast you have, the cast will take either 30 minutes or 24 hours to dry after it is first fitted. Your doctor will tell you what kind of cast you have. It is important that you don't put any weight on the cast while it's drying.
You should do as little walking as possible after the cast dries. The reasons are:
- The ulcer will heal faster if you put less pressure on it.
- Your leg with the cast is longer than your other leg. This can cause pain in your hip or back if you walk too much.
- You're less stable when you're wearing a cast. Your chances of falling and hurting yourself are increased. The less you walk, the less likely you are to fall. Be very careful on slippery or uneven ground. Use a cane for added stability even if you usually don't use a cane. If you were already unsteady before wearing the cast, it is a good idea to use a walker.
Can I get my cast wet?
No. You won't be able to take regular baths or showers because you have to keep the cast dry. Take sponge baths instead.
Try not to go outside when the weather is wet. If you must go outside when it's wet, wrap your cast in a plastic bag.
When should I call my doctor?
Remember that you don't have good pain sensation (ability to feel pain) in your leg, so you might not be able to feel if something is going wrong. You must check your cast (or have someone else check it) every day. Call your doctor if you notice any of the following:
- The cast is loose. The cast should fit your leg very tightly. If it becomes loose, it could rub against your leg or foot and cause a new sore. A space of more than 1/4 inch between your cast and your leg is too much.
- Dents, cracks and other damage to the cast. A dent or other damage can apply dangerous levels of pressure to your leg, and you might not be able to feel it.
- A smell coming from the cast. This could be a sign of an infection that started after your doctor put the cast on.
- Fever (temperature of 100°F or higher) or a sudden, unexplained increase in your blood sugar levels.
You should also call your doctor if:
- You are having a lot of pain in your back or hip.
- You get the cast wet.
- You are having problems with your balance.
Is there anything else I should know?
A few other tips may help you. You may have some itching under the cast. Don't slide anything down the cast to scratch the itch because you could very easily damage the skin underneath.
When you're sitting down, put your leg up on a chair or pillow whenever possible.
While you're sleeping, you might kick or rub your other leg with the cast. This could cause skin damage on your other leg. It is a good idea to put a thick, soft knee-high sock over your other leg before you go to bed, or put a pillow between your legs.
If you would like more information on how diabetes affects your feet, ask your doctor.
Written by familydoctor.org editorial staff