Ganglion cyst

What is a ganglion cyst?

A ganglion cyst is a collection of fluid on a joint or tendon. Tendons are tissues that connect muscles and bones. Ganglion cysts usually appear on parts of the body including:

• the backs of hands
• the fingers
• the wrists
• the feet
• the ankles
• the knees

Ganglion cysts are more common in women than men. They usually occur in young to middle-aged adults.

What are the symptoms of a ganglion cyst?

A ganglion cyst looks like a smooth lump under the skin. They can range from pea-sized to golf ball-sized. Occasionally they might not be visible at all.

Most ganglion cysts do not cause symptoms, but sometimes they cause:

• pain or tingling
• muscle weakness
• a pinched nerve

These symptoms can come from pressing or stretching of the affected area.

Ganglion cysts on the foot are usually painful due to walking or wearing shoes. Ganglion cysts on the wrist, hands or fingers can cause pain that moves up into the arm.

What causes ganglion cysts?

The cause of ganglion cysts 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.

When should I see a doctor?

Many people with ganglion cysts never bother having them treated. Treatment is not necessary, and they sometimes go away by themselves after a couple of years.

If the cyst is causing you pain, or affecting your mobility, you should see a doctor.

How are ganglion cysts diagnosed?

If you think you have a ganglion cyst, it is important to see your doctor. They will 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
• an ultrasound to find out whether the lump is solid or filled with fluid
• an MRI to examine a cyst that is not visible

How are ganglion cysts treated?

If you do need treatment for your ganglion cyst, there are some options.

Using a needle, your doctor can drain the fluid from the cyst (aspiration). This is a quick and simple procedure. It can be done in your doctor’s office. Roughly half of ganglion cysts removed this way will come back.

You can also have surgery to remove 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 injuries and will be very painful.

Can ganglion cysts be prevented?

Because the cause of ganglion cysts is not known, they cannot be prevented.

Complications of ganglion cysts

Ganglion cysts usually do not cause complications. However, they can sometimes:

• cause pain
• make it difficult to move the affected part of your body

You can visit your doctor if you experience these complications.