The most common benign soft tissue mass of the hand and wrist is a ganglion cyst. The majority of ganglion cysts occur on the back of the hand at the wrist joint but they can also develop in other locations. Ganglion cysts may be found inside the front of the wrist, at the base of the fingers on the palm, and in the fingertip just below the cuticle. Although most frequently seen in the hand and wrist, ganglion cysts may also develop on the outside of the knee and ankle or on the top of the foot.
Ganglion cysts consist of a stalk topped by a balloon-like sac filled with a gelatinous fluid. They emerge from the tissues that surround a joint, such as ligaments, tendon sheaths, and joint linings. Ganglion cysts are typically round or oval. Although most form a visible lump, smaller ganglion cysts can remain hidden under the skin. A ganglion cyst may develop as a single large cyst or on occasion as multiple smaller ones connected by a common stalk in the deeper tissues. The size of the cyst can fluctuate from one that is very small to a cyst that is larger and more unsightly. Most of the time a ganglion cyst measures less than an inch in diameter.
The exact cause of a ganglionic cyst is not known. It may be related to trauma, a flaw in the joint capsule or tendon sheath, or in some cases associated with degenerative changes. Ganglion cysts can occur in all age groups but are more common among individuals in between the ages of 15 and 40 years. They are also seen more frequently in women than men.
Many ganglion cysts do not produce symptoms other than a noticeable bump. However, depending on location and size of the cyst localized discomfort and mechanical symptoms such as limited joint motion may occur. If a ganglion cyst is impinging on nerve the result may be feelings of tingling, burning, numbness, and muscle weakness. When the cyst is pressing on a tendon or a joint a dull pain or ache may be experienced.
Whether or not a persistent mass has associated symptoms, it should be evaluated. Often the doctor can diagnose a ganglion cyst based on a history and physical examination. However, in order to rule out other disorders or tumors further diagnostic tests, including imaging studies and aspirating a sample of the cyst fluid, may be ordered.
If once diagnosed, a ganglion cyst is small and causes no discomfort, the doctor may decide to place it under observation. Some cysts resolve without treatment. However, if there are symptoms of discomfort and limited joint movement, treatment may be recommended.
Treatments for a ganglion cyst may involve:
- Immobilization with a wrist brace or splint to prevent movement, which might relieve symptoms and further aggravation of the cyst.
- Aspiration to drain all the fluid from the ganglion cyst
- Surgery to remove the cyst and the stalk that attaches it to the joint or tendon
Although there is a high success rate associated with the treatment of ganglion cysts, there are cases where they recur and require additional care.