Ganglion cysts are very common lumps within the hand and wrist that occur adjacent to joints or tendons. The most common locations are the top of the wrist, the palm side of the wrist, the base of the finger on the palm side, and the top of the end joint of the finger. The ganglion cyst often resembles a water balloon on a stalk , and is filled with clear fluid or gel.
The cause of these cysts is unknown although they may form in the presence of joint or tendon irritation or mechanical changes. They occur in patients of all ages.
These cysts may change in size or even disappear completely, and they may or may not be painful. These cysts are not cancerous and will not spread to other areas.