A ganglion cyst is a fluid-filled swelling that forms on a tendon or in a joint. Most don't cause any problems, and many go away on their own within about a year. If a ganglion cyst causes your child pain or trouble with movement, your health care provider may recommend draining fluid from the cyst with a needle or surgery to remove it. 

• Your child can continue all regular activities but if an activity (such as playing video games, using computers, or playing sports) causes pain or makes the ganglion cyst bigger, they may need to limit that activity or take a break from it.
• If the ganglion cyst hurts and your health care provider says it's OK, you can:
  • Put an ice pack wrapped in a towel on the area for about 15 minutes, 3 times a day.
  • Give your child acetaminophen (Tylenol^® or a store brand) or ibuprofen (Advil^®, Motrin^®, or a store brand). Follow the package directions for how much to give and how often.
• If your health care provider recommended wearing a brace, help your child use it as instructed. Using a brace too long can weaken the muscles, so your child shouldn't use it longer than recommended.
• Do not push on or hit the cyst to try to make it go away. 
• Follow up as recommended by your health care provider.

Your child has:

• new or worse pain or trouble moving the joint
• numbness (loss of feeling) or a "pins and needles" feeling in the area (this could be a sign that the ganglion cyst is squeezing the nerve in the joint)

What causes ganglion cysts? The exact cause isn't known. Repeated movements may make a ganglion cyst swell, but doctors don't think this causes the cyst to develop.

What are the symptoms of a ganglion cyst? Some people might notice a bump where the ganglion cyst is. The bump may get a little bigger or smaller over time. A ganglion cyst can also cause pain or squeeze the nerve in the joint.

Can ganglion cysts come back? Ganglion cysts can come back. This is more likely to happen if it is drained or removed by surgery than if it goes away on its own.