2) Signs and Symptoms: Most patients notice a lump under the skin which most commonly is located on the back side of the wrist, on the palm side of the wrist, over a tendon at the base of a finger on the palm side, or on a finger at the joint closest to the fingertip. Ganglia are often painless; however, they may cause pain with movement or cause mechanical problems (limiting range of movement) depending on where they are located. They have a tendency to wax and wane in size, presumably as the fluid contained within the cyst drains back into the joint or tendon sheath and again produces fluid and fills. The biggest problem with a ganglion may be the fear a patient may have that it is something more ominous. The diagnosis is based on the history, physical examination, and possibly plain x-rays or ultrasound. The cyst can be distinguished from a solid tumor by transillumination (light will pass through the hollow fluid filled ganglion, but not a solid tumor mass). Ultrasound imaging has also been used to differentiate between solid and cystic masses in the hand.
- Possible Causes: The cause of ganglia is not completely understood, and there have been conflicting views on their origin. As mentioned earlier, ganglia can occur when there is a small tear in the ligament overlying a tendon sheath or joint capsule. Whether this is due to injury, a degenerative process, or a subtle abnormality is unknown.