Ganglion cysts are extremely common conditions that occur about the hand and wrist. They can be found on nearly every part of the hand and wrist. They can be large or small, are usually painless, but sometimes they can cause problems. Because the cysts may be painless, people may wait long periods of time before noticing them.
Ganglion cysts usually originate from a joint. Every joint is covered with a capsule and connected with ligaments. Sometimes, because of trauma, or for no reason at all, a small hole in the covering of the joint develops, and the fluids in the joint starts to escape. This forms a balloon or sack with fluid entering the sack. Over time the sack can become thickened and the fluid within it can become thickened as well. In fact, the fluid within the cyst becomes gelatinous jelly like.
Ganglion cysts that appear in the back of the wrist are called “dorsal ganglionic cysts” and those that occur on the palm side of the wrist are called “volar ganglionic cysts.” Cysts that occur within the tendons of the hand are called “retinacular cysts.” When they appear at the tip of the finger beneath the nail they are called “mucous cysts.”
Ganglion cysts can usually be diagnosed easily with a history and physical examination. X-rays and MRIs are usually not needed; however, if there is any question your doctor will likely order an MRI to rule out any other conditions that may be more serious. Often a simple flashlight test can help diagnose the ganglionic cyst. Since the cyst is filled with fluid, placing a light at the base of the mass will cause the ganglionic cyst to illuminate, which is helpful in making the diagnosis.
There are a variety of treatments available for ganglionic cysts, but the most important decision is whether to treat it at all. Reasons for treating ganglionic cyst include that the cysts that are painful, cysts may be causing damage to structures in the area such as nerves, arteries or tendons, uncertainty about the diagnosis, and cosmesis. Many people have the cyst removed because they don’t like it or don’t like the way it looks, and this is reasonable.
The main treatments available for ganglionic cysts include aspiration or excision. Aspiration of the cyst involves putting a needle in the cyst cavity and removing the fluid. As you can imagine, while this removes the fluid, it leaves the sack in place, which is sometimes absorbed by the body, but at other times it refills with fluid. A more definitive way to remove the cyst is to take it out surgically. This is often done under local anesthesia with a small incision; however, in certain places it can be done arthroscopically.
The most important take-home message about ganglionic cyst is making the correct diagnosis. If there is any question that it is not a cyst, you should see your doctor.