Fluid from a joint or around a tendon gets trapped, forming a balloon-like structure that appears as a swelling or bump.

Ganglion cysts are benign (not cancerous) tumors that occur near joints or tendons.  They are the most common “lumps” found in the hand.  Ganglion cysts can be seen in any age group, and are found more often in women. The cysts are firm sacs filled with a clear jelly-like fluid.  In the fingers, near the nail, they can be called mucous cysts.  The size of the cyst(s) may vary; at times they may even seem to disappear.

Fluid from a joint or around a tendon gets trapped, forming a balloon-like structure that appears as a swelling or bump.  The lump can get larger with use of the joint or tendon it is attached to; often getting tender as its size increases.  The actual cause is controversial; some appear after an injury or with arthritis, most have no apparent cause.

The lump itself is the usual reason ganglion cysts are noticed.  There is typically no pain at rest, but the cyst may be tender with activity.  Occasionally, numbness or tingling is associated with ganglions, especially with the larger ones. Common locations include the wrist or in the fingers.

A non-painful lump or bump found adjacent to a joint or tendon is usually a ganglion cyst.  If a needle is stuck in the cyst, a clear jelly-like fluid is found.  The lump may get tender with use.  Fluctuation in size is also consistent with ganglion cysts.  X-rays are normal in the uncomplicated ganglion cysts. Ganglion cysts in the fingers are sometimes called mucous cysts and can be associated with arthritis.  MRI is occasionally useful to localize small, suspected ganglions.

Ganglions can be observed over time; alternatively some can be drained with a needle.  The ones in the fingers tend to recur after drainage; therefore, surgery is the standard treatment of ganglions in the fingers. Ganglions in the hand or finger are removed in the office under a local anesthetic. This is not only much less costly than surgery in the hospital or operating room, but is equally effective and safe. Wrist ganglions are removed in the operating room in either the hospital or outpatient surgery center.