A ganglion cyst – usually just called a ganglion - is a harmless fluid-filled sac that can pop up anywhere on the body but is common around the joints and tendons of the hand and wrist. They are three times more common in women than men between the ages of 20 and 40, and 80% of them are found in the wrist.
It is thought they are caused by fluid leaking out of a joint or the tunnel of a tendon, and this causes a swelling below the skin. This is typically synovial fluid – the same substance found in joints to keep them lubricated. The leak may be caused by trauma or arthritis.
While lumps and bumps often cause alarm, ganglions pose no risk to your health, and people are often more bothered by their appearance than from any symptoms. (You may occasionally get discomfort or difficulty with certain movements if the ganglion is around a joint.)
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A ganglion will cause no problems with normal activities for the majority of people and around half of them will gradually disappear without any treatment. If your ganglion is causing pain or difficulty with movement of a joint then try taking simple painkillers.
You are fit for work if you have a ganglion cyst.
If your ganglion is causing significant pain or problems with movement, and simple measures have not helped, see your doctor. Ganglion cysts can be tricky to treat, and your doctor may refer you to a specialist for further treatment if the ganglion is causing you significant symptoms. One technique is to use a fine needle to drain the cyst of fluid, but the lump may return. Surgical removal is occasionally offered for painful ganglion cysts, but again, there's a risk of it just coming back.
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