The cause of them is not known, however it is thought they may be caused by tiny tears in the covering of a tendon or joint. Ganglion cysts are benign, meaning they are not cancerous.
Ganglion cysts symptoms
A ganglion cyst looks like a smooth lump under the skin, ranging in size from the size of a pea to the size of a golf ball. Occasionally they might not be visible at all.
Most ganglion cysts do not cause symptoms, but sometimes they cause:
- difficulty moving the affected area
- a pinched nerve.
Ganglion cysts diagnosis
If you think you have a ganglion cyst, it is important to see your doctor to make sure that the lump is not a symptom of another illness. An examination by your doctor is generally all that is needed.
Other possible tests include:
- removing some of the fluid with a syringe
- ultrasound to find out whether the lump is solid or filled with fluid
- MRI to examine any cyst that is not visible
Ganglion cysts treatments
Many people with ganglion cysts never bother having them treated. Sometimes they go away by themselves after a couple of years.
Treatment isn’t necessary unless a cyst is causing pain or making it difficult to move the affected part of your body.
If you do need treatment, here are some options:
- Using a needle to drain the fluid out of the cyst (aspiration). This is a painless procedure that can be done in your doctor’s office or in a hospital outpatient department. Roughly half of ganglion cysts removed this way will come back.
- Surgery to cut out the cyst. This is a simple procedure that can be done under local or general anaesthetic. A small number of people have ongoing pain and stiffness in the area after surgery.
The traditional method of treating a ganglion cyst involves hitting it hard with a heavy book. This is not a good idea. It might burst the cyst, but it might cause other injury.
Last reviewed: October 2015