Ganglia are swellings on the hands and wrists that contain a jellylike fluid.
Ganglia typically spontaneously occur in people between the ages of 20 and 50. Women are affected 3 times more often than men. Ganglia usually develop on the back of the wrist. Ganglia also develop on the front of the wrist and on the back of the finger, a few millimeters behind the cuticle (where they are also called mucous cysts).
Why ganglia develop on the wrist is not known, although they may be related to a previous injury. Ganglia on the back of a finger usually are related to arthritis of the last joint of the finger. However, in most cases, having a ganglion cyst does not mean that arthritis will develop.
Ganglia are firm, smooth, and round or elliptical swellings that rise from the skin surface. They contain a clear, jellylike, and usually sticky fluid. They are usually painless but occasionally cause discomfort. A doctor can readily make the diagnosis by examining the hand.
Most ganglia disappear without treatment, so treatment may not be necessary. However, if they are unsightly, cause discomfort, or continue to increase in size, the jellylike fluid inside them can be removed successfully by a doctor using a needle and a syringe (called aspiration). Aspiration is effective in about 50% of people. Sometimes a corticosteroid suspension is injected afterward to further ease any discomfort. The traditional method of removing a ganglion—placing the hand on a firm surface (such as a table) and hitting the ganglion with a large book or other hard object—is not advisable. This method may cause injury and is unreliable. In about 50% of people, surgical removal may be necessary. After surgical removal, ganglia recur in about 5 to 15% of people.
Last full review/revision September 2013 by David R. Steinberg, MD