Overview

Ganglion cysts are lumps that most often appear along the tendons or joints of wrists or hands. They also can occur in ankles and feet. Ganglion cysts are typically round or oval and are filled with a jellylike fluid. They are not cancer.

Small ganglion cysts can be pea-sized. They can change size. Ganglion cysts can be painful if they press on a nearby nerve. Sometimes they affect joint movement.

For a ganglion cyst that causes problems, having a health care provider drain the cyst with a needle might be an option. So might removing the cyst surgically. But if there are no symptoms, no treatment is necessary. Often, the cysts grow and shrink. Some go away on their own.

Symptoms

These are common features of ganglion cysts:

  • Location. Ganglion cysts most often develop along the tendons or joints of wrists or hands. The next most common locations are the ankles and feet. These cysts grow near other joints too.
  • Shape and size. Ganglion cysts are round or oval. Some are too small to feel. The size of a cyst can change, often getting larger over time with joint movement.
  • Pain. Ganglion cysts usually are painless. But if a cyst presses on a nerve or other structures, it can cause pain, tingling, numbness or muscle weakness.

When to see a doctor

See a health care provider if you notice a lump or pain in your wrist, hand, ankle or foot. You can get a diagnosis and find out whether you need treatment.

Causes

No one knows what causes a ganglion cyst. It grows out of a joint or the lining of a tendon and looks like a tiny water balloon on a stalk. Inside the cyst is a thick fluid like the fluid found in joints or around tendons.

Risk factors

Factors that may increase the risk of ganglion cysts include:

  • Sex and age. Ganglion cysts can develop in anyone, but they most often occur in women between the ages of 20 and 40.
  • Osteoarthritis. People who have wear-and-tear arthritis in the finger joints closest to the fingernails are at higher risk of developing ganglion cysts near those joints.
  • Joint or tendon injury. Joints or tendons that have been injured are more likely to develop ganglion cysts.
By Mayo Clinic Staff