Treatment:

Often no treatment is needed. The health care provider can watch the cyst over time.

If the cyst is painful, the goal of treatment is to correct the problem, such as arthritis or a meniscus tear. The cyst is usually not removed because it can come back. The surgery may also damage nearby blood vessels and nerves.

Sometimes, a cyst can be drained (aspirated) or, in rare cases, removed with surgery if it becomes very large or causes symptoms.

Expectations (prognosis):

A Baker's cyst will not cause any long-term harm, but it can be annoying and painful. The symptoms of Baker's cysts usually come and go.

Long-term disability is rare. Most people improve with time or arthroscopic surgery.

Complications:

Complications are unusual, but may include:

• Long-term pain and swelling
• Complications from related injuries, like meniscal tears

Calling your health care provider:

Call for an appointment with your health care provider if you have swelling behind the knee that becomes large or painful. Pain could be a sign of infection.