Getting a cast often comes with plenty of questions. Here are
answers to some frequent inquiries many parents - and kids - have
about casts.
What are the different kinds of casts?
A cast, which keeps a bone from moving so it can heal, is
essentially a big bandage that has two layers - a soft cotton layer
that rests against the skin and a hard outer layer that prevents
the
broken bone
from moving.
These days, casts are made of either:
- plaster of paris:
a heavy white powder that forms a thick paste that hardens
quickly when mixed with water. Plaster of paris casts are heavier
than fiberglass casts and don't hold up as well in
water.
- synthetic (fiberglass) material:
made out of fiberglass, a kind of moldable plastic, these casts
come in many bright colors and are lighter and cooler. The
covering (fiberglass) on synthetic casts is water-resistant, but
the padding underneath is not. You can, however, get a waterproof
liner. The doctor putting on your child's cast will decide
whether a fiberglass cast with a waterproof lining is
appropriate.
How is a cast put on?
First, several layers of soft cotton are wrapped around the
injured area. Next, the plaster or fiberglass outer layer is soaked
in water. The doctor wraps the plaster or fiberglass around the
soft first layer. The outer layer is wet but will dry to a hard,
protective covering. Doctors sometimes make tiny cuts in the sides
of a cast to allow room for swelling.
Can plaster of paris casts get wet?
Absolutely not! A wet cast may not hold the bone in place
because the cast could start to dissolve in the water and could
irritate the skin underneath it, possibly leading to infection. So
your child shouldn't swim and should use a plastic bag or
special sleeve (available online or sometimes at pharmacies) to
protect the cast from water. And instead of a shower, your child
may need to take a sponge bath.
Can synthetic (fiberglass) casts get wet?
Although the fiberglass itself is waterproof, the padding inside
a fiberglass cast is not. So it's still important to try to
keep a fiberglass cast from getting wet. If this is a problem, talk
to the doctor about getting a waterproof liner. Fiberglass casts
with waterproof liners let kids continue bathing or even go
swimming during the healing process. Although the liner allows for
evaporation of water and sweat, it's still fragile. Also, only
certain types of breaks can be treated with this type of cast. Your
doctor will determine if the fracture may be safely treated with a
waterproof cast.
Is it OK to have people sign and draw on my child's
cast?
Definitely! That often makes the whole broken bone experience
more bearable for kids. Permanent markers usually work best;
washable ones can smear. Feel free to encourage siblings, family
members, and classmates to sign it, draw pictures on it, or
decorate it with stickers. The doctor might even let your child
keep the adorned cast as a souvenir.
What if my child has an itch in the cast?
Try blowing some air in the cast with a hair dryer - be sure to
use the cool setting, though. And you should
never
pour baby powder or oils in the cast to try to relieve itching or
try to reach the itch with long, pointed object such as a pencil or
hanger - these could scratch or irritate your child's skin and
can lead to an infection.
What if the cast gets a crack?
This can happen if the cast is hit or crushed, has a weak spot,
or if the injured area begins to swell underneath. Call your doctor
as soon as you notice a crack. In most cases, a simple repair can
be done to the cast without needing to remove it or change it.
What if the cast causes my child's fingers or toes to turn
white, purple, or blue, or if the skin around the edges of the cast
gets red or raw?
The cast may be too tight. Redness and rawness are typically
signs that the cast is wet inside, from sweat or water. Sometimes,
kids pick at or remove the padding from the edges of fiberglass
casts. They shouldn't do this, though, because the fiberglass
edges can rub on the skin and cause irritation. Call your doctor to
have the problem fixed right away.
Why aren't some types of broken bones put in casts right
away?
Some kinds of fractures don't need casts to heal. Certain
fractures of larger long bones, such as the femur (thighbone), are
hard to keep straight in a cast. Although doctors used to commonly
put many of these kinds of fractures in traction (a way of gently
pulling the bone straight), these days, surgery is often used
instead.
Do all broken bones need casts?
It's not practical to cast ribs and collarbones (clavicles).
Even displaced collarbones (in which pieces on either side of the
break are out of line) heal well with a sling or special strap
called a "figure-of-eight clavicle strap," which the
child wears like a vest. Some non-displaced finger and toe
fractures (in which the pieces on either side of the break line up)
that don't involve the joint or the growing part of a
child's bone (called the growth plate) may heal well with a
splint or buddy taping (taping the injured digit to the adjacent
unaffected finger or toe).
Will my child feel pain when the broken bone is in a cast?
Some pain is expected for the first few days, but it's
usually not severe. The doctor may recommend acetaminophen or
ibuprofen to ease pain.
How are casts taken off?
The doctor will use a small electrical saw to remove the cast.
Although it may look and sound scary to your child, the process is
actually quick and painless. The saw's blade isn't sharp -
it has a dull, round blade that vibrates up and down. The vibration
is strong enough to break apart the fiberglass or plaster, but
shouldn't hurt your child's skin and may even tickle.
What will the injured area look and feel like when the cast is
removed?
Once the cast is off, the injured area will probably look and
feel pretty weird to your child: The skin will be pale, dry, or
flaky; hair will look darker; and the area (muscles especially)
will look smaller or weaker. Don't worry, though - this is all
temporary. And depending on the type and location of your
child's fracture, the doctor may also give your child special
exercises to do to get the muscles around the broken bone back in
working order.
Reviewed by:
Steven Dowshen, MD
Date reviewed: November 2007
Originally reviewed by:
Peter G. Gabos, MD
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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