In the hand, a ganglion is a particular type of lump which shows up next to a joint or a tendon. Inside, it is like a balloon filled with a thick liquid. It may be soft or hard, may or may not be painful, and may get bigger or smaller on its own. It may also be referred to as a mucous cyst, a mucinous cyst or a synovial cyst.
Normally, joints and tendons are lubricated by a special liquid which is sealed in a small compartment. Sometimes, because of arthritis, an injury, or just for no good reason, a leak occurs from the compartment. Now, the liquid is thick, like honey, and if the hole is small, it can be like having a pinhole in a tube of toothpaste - when you squeeze the tube, even though the hole is small and the toothpaste is thick, it will leak out - and once it is out, there is no way it can go back in on its own. It works almost like a one way valve, and fills up a little balloon next to the area of the leak. When we use our hands for normal activities, our joints squeeze and create a tremendous pressure in the lubricating compartment - this can pump up a balloon leak with so much pressure that it feels as hard as a bone.
The lubricating liquid has special proteins dissolved in it which make it thick and also make it hard for the body to absorb it when it has leaked out. The body tries to absorb the liquid, but may only be able to draw out the water, making it even thicker. Usually, by the time the lump is big enough to see, the liquid has gotten to be as thick as jelly.
Common sites for ganglions are:
•The wrist - on the back ("dorsal wrist ganglion"), on the front ("volar wrist ganglion"), or sometimes on the thumb side. These come from one of the wrist joints, sometimes aggravated by a wrist sprain.
•The palm at the base of the finger ("flexor tendon sheath cyst"). These come from the tube which holds the finger tendons in place, and are often due to tendon irritation - tendinitis.
•The back of the end joint of the finger ("mucous cyst"), next to the base of the fingernail. These can cause a groove in the fingernail, or rarely can become infected and lead to a joint infection. These are usually due to some arthritis or bone spurs in the joint.
What Can You Do?
Wait and watch.
"Over the counter" non-steroidal anti inflammatory medication (NSAID), such as aspirin, ibuprofen, naprosyn, or ketoprofen. Check with your pharmacist regarding possible side effects and drug interactions.
Some people, following non-medical advice, will smash the lump with a heavy book, and rupture the cyst. Sometimes this works, but I don't recommend it. The lump can come back even if it has been successfully treated this way. The urban legend regarding this traditionally involves using a Bible as the book, leading ganglions to be called "Giddeon's disease" in some circles.
Some people attempt to drain the cyst by sticking it with a needle - particularly when the cyst is on the end joint of the finger. Don't try this at home! It can lead to a serious infection in the joint.
What Can a Doctor Do?
Confirm that this actually is the problem.
Prescribe a custom prescription splint.
Drain the cyst with a needle and possibly inject the area with cortisone. This works much better for cysts coming from the tendon than those coming from joints.
Perform surgery to remove the cyst and clean out the area where the cyst comes from.
How Successful it Treatment?
It depends on several things.
Tendon sheath cysts are more likely to be cured with a cortisone shot than cysts coming from joints.
Cysts coming from joints are less likely to come back after surgery if the joint itself is "cleaned out", but cleaning the joint out increases the chance that the joint will be somewhat stiff after surgery. For example, cysts on the back of the wrist come back about one out of three times give the joint is not cleaned out, but only about one out of twenty times if the joint is cleaned out.
What Happens if You Don't Have Treatment?
This depends on what kinds of problems you're having, but it is a good idea to have your cyst checked out by a doctor and possibly have x-rays to make sure that you are not ignoring a potential health problem. For example,
Painful cysts may be painful because of underlying problems other than a simple cyst. Although uncommon, pain associated with a ganglion may be due to underlying arthritis, bone tumor, ligament injury or fracture.
Cysts can extend into the underlying bones and cause other types of problems.
Cysts on the back of the end joint of the finger (mucus cysts) may gradually thin and weaken the overlying skin, allowing liquid to drain out but also allowing bacteria to enter the joint, sometimes causing a serious infection.
Once these types of issues have been evaluated by a physician, the choice is yours. Most ganglions do not pose a serious health risk, and can be simply left alone. Many ganglions go away on their own. Between one-third and two-thirds of wrist ganglions eventually go away with no treatment.