Mom! This thing itches!

Published: January 27, 2017 | Updated: October 12, 2020

What do Corvettes and broken arms have in common? Those slick cars and that fancy new cast your child is wearing are likely made out of the same fiberglass.

Pretty cool, huh?

Maybe, but that’s little or no consolation if you’re now dealing with an unhappy child whose life has been altered for the next several weeks.

You and your child might not be in love with your new fiberglass companion, but you still want to take good care of it. Otherwise, you might keep the injury from healing, cause other injuries or require an entirely new cast.

“The inside of a cast is lined with a stocking and then padded with soft cast padding so bony joints don’t rub against the hard fiberglass,” said Laura Jacks, M.D., pediatric orthopedic surgeon with Children’s Orthopedics of Louisville. “The stocking and padding can absorb water and other liquids, so they should be kept as dry as possible.”

The best way to avoid accidental leaks is to avoid water altogether, but since you don’t want a smelly child for the foreseeable future, Dr. Jacks offers some tips:

• Cover the cast with two plastic bags. Check each bag first to be sure it doesn’t leak. Seal the top of each bag to the skin with tape.

• Even with the cast covered, never dunk the cast in water. The bag will repel a splash but usually won’t survive a dunking. Commercial cast covers are available at medical supply retailers or online.

• If the cast does get wet, blot it dry as best you can. Let the water run out first, then blow cool air from a hair dryer in the ends.

• Be sure the air is cool. A warm blow dryer can burn skin. If the cast is too wet, even after drying, it may cause the skin under the cast to break down. The only way to fix this is to change the whole cast.

• Itching under the cast is very common. Tapping the outside of the cast can satisfy some itches. Don’t use a pen to scratch inside — the top may come off inside the cast and leave a nasty bruise on the skin where it is stuck. Benadryl or Zyrtec can help the itch feel better, especially if it is keeping your child up at night.

• If you are allowed to walk on a leg cast, make sure you cover the foot of the cast with a shoe or something else. The cast bottom is slick, and without something between it and the ground, you could fall and break something else.

The good news is it’s still OK to turn your child’s cast into a work of art.

“We strongly encourage your child to have fun and decorate the cast,” Dr. Jacks said. “We would love to see the artwork when you return!”