Unless you have a waterproof cast, you should keep your cast dry.
However, even waterproof casts should be dried out thoroughly after
getting them wet. If you don't dry your cast out after getting it wet,
the skin underneath stays damp and can become moldy and smelly. Also,
don't swim with your cast on unless you have the waterproof kind.
To keep your cast dry in the shower, you can enclose it in a plastic
garbage bag. Tape the open end of the bag so that water can't get in.
You can also buy a special cast protector.
Casts don't completely harden for about two days. Be especially
careful with your cast during this time. Don't rest the full weight of
the cast on a hard surface during these first two days. Doing so can
dent the cast and can cause pressure sores on the skin under the cast.
If the cast involves your foot, don't walk on it for forty-eight hours,
even if you have what is known as a walking cast. Walking on a soft cast may cause it to crack or dent.
Keep the casted or splinted limb elevated (propped up) above
the level of your heart when you're able to do so. This will reduce the
swelling and help to keep the cast from becoming too tight.
Avoid too much activity and situations that may re-injure you or
damage your cast. Remember your cast is there to help your arm or leg
heal. It can't do its job without your cooperation.
If you have any of the following warning signs after your cast is placed or changed, you should consult your doctor.
Severe Pain
Your injury will probably cause some pain,
but if the pain becomes steadily worse after the cast has been placed
or changed, that may be a sign that the cast is too tight.
Bluish Nailbeds
The area under the fingernails and toenails is called the nailbed.
Normally the nailbeds are pink. When the nailbed is pinched and
released, it turns white for a few seconds and then pink again. This is
because small blood vessels under the nail are squeezed shut. When you
release the pressure, the blood vessels quickly open back up, turning
the nail bed pink once again. This is called blanching. If the nailbed has a blue color and doesn't turn pink again after being pinched and released, this may be a warning sign that the cast is too tight.
Numbness or Tingling
You may feel some numbness
after a broken bone has been straightened or fixed if any type of
anesthesia (such as a regional block or local anesthesia) was used.
This should wear off in a few hours. But if you feel constant numbness
or tingling in the fingers or toes of the casted arm or leg, this may
indicate that the cast is too tight or that a nerve has been injured.
Immobility of Fingers or Toes
Because of your injury, you may have pain that makes it difficult for you to move your fingers or toes. But if you have no ability to move
the fingers or toes of the casted arm or leg, it may be a signal that
the cast is too tight and the muscles or nerves aren't working properly.
Severe Coolness of Fingers or Toes
Many people notice a difference in the temperature of the casted arm
or leg. Usually, this difference is minor. But if you have any other
problems mentioned here that suggest that the circulation is not good,
and the hand or foot is cool, it may be a sign that the cast is too
tight.
Severe Swelling
If you have severe swelling above or below your cast, try keeping
the casted limb propped up above the level of your heart. Most injuries
cause at least some swelling.
But if the swelling continues to get worse after the cast is put on, it
may be either a sign that the cast is too tight or that something is
going on under the cast that needs to be checked.
Dented or Cracked Cast
If your cast is dented or cracked,
or starts falling apart before you are due for a checkup, this could
lead to problems with healing. Small cracks are probably alright, but
if the cast isn't doing what it is supposed to, it could affect the
healing of the injury. You should also check with your doctor if you
think the cast isn't holding the arm or leg still enough.