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What is a ganglion?

A ganglion is a sac-like swelling or cyst formed from the tissue that lines a joint or tendon. The tissue, called synovium, normally functions to produce lubricating fluid for these areas. A ganglion is a cyst formed by the synovium that is filled with a thick jelly-like fluid. While ganglia can follow local trauma to the tendon or joint, they usually form for unknown reasons. Occasionally, ganglia are early signs of arthritis that will become more obvious in the future.

What are ganglion causes and risk factors?

Ganglions can be caused by inflammation of the tissue lining joints and tendons. This inflammation can be a result of local injury or underlying arthritis.

Where do ganglia form and what symptoms do they cause?

Ganglia can form around any joint, but they are most frequently found in the wrist and ankles. They are usually painless and often barely visible as localized swellings. They typically do not appear to be inflamed. The largest ganglions form behind the back of the knee, causing a sense of fullness or tightness. A ganglion here is referred to as a Baker cyst, after the doctor who originally described the condition.

What specialists treat a ganglion?

Specialists who treat ganglions include primary-care providers such as general medicine doctors, family medicine doctors, and internists, as well as rheumatologists and general and orthopedic surgeons.

How do doctors diagnose and assess a ganglion?

Doctors diagnose a ganglion by physical examination. These ganglions can usually be felt on examination. A ganglion can be a result of underlying arthritis of the adjacent joint, and X-ray analysis is often used to determine the integrity of joints affected.

Medically Reviewed by a Doctor on 8/23/2016



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