A ganglion cyst is a soft tissue mass that is filled with a protein-rich fluid. They are walled off from the surrounding soft tissues with a thin wall, and may be single or multi-chambered. Ganglion cysts are most commonly found on the backs of the hands and wrists, or on the top of the foot and ankle. They can sometimes be worrisome to the patient when they develop, but it should be comforting to the patient to know that they are benign and usually harmless.
Ganglion cysts can develop in a variety of different tissues, including nerves, tendons, and joints. The exact mechanism of their development is not completely understood, but they are usually attributed to repetitive trauma. In the foot and ankle, an irritating shoe may be the cause.
The symptoms are dependent on which structures are affected and on the size of the growth. If nerves ate involved, there may be a bunring or tingling sensation, or the area may go numb. There is typically pain involved in any ganglion cyst, particularly when they grow in size and become irritated.
Historically, ganglion cysts used to be referred to as “bible bumps”. This is due to the fact that they used to be treated by slamming a large book, such as a bible, onto the back of someone’s hands with a ganglion cyst. Not surprisingly, this turns out to be a terrible treatment for ganglion cysts. It leads to a high rate of recurrence, and is probably quite painful.
Today, ganglion cysts are treated in a more precise manner. X-rays are typically taken as a first line diagnostic exam to rule out other pathological processes, such as invasive tumors, malignancy, and soft tissue calcifications. Ultrasound is becoming more popular as a diagnostic exam for ganglion cysts, as it is a quick, easy, and inexpensive method of visualizing the cyst beneath the skin. MRI may be used as well, but is more expensive, time consuming, and is generally reserved for surgical planning.
Treatment of a ganglion cyst usually begins with aspiration of the cyst with a small needle. Removing the fluid can relieve some of the pressure on the area, as well as serve as a definitive diagnosis. The area is typically numbed prior to aspiration, to provide comfort for the patient. A steroid is often injected into the area as well to reduce swelling and inflammation. Padding the area may also prove to be helpful in treatment, but is usually not sufficient on its own.
Some ganglion cysts may require surgical removal for complete relief. It should be noted, however, that the recurrence of ganglion cysts is very high in both surgical and non-surgical treatment.