A ganglion cyst is a mass or lump that forms below the surface of the skin. It is a benign cyst that is filled with a jelly-like fluid. The term ganglion means “knot”. It is not a malignant tumor, but a soft tissue benign mass. Ganglion cysts can occur anywhere; however, they usually occur at the wrist area and may occur at the foot (usually on top). This mass can change in size, vary in size, and may grow slowly.
Presentation
The mass is usually asymptomatic and typically, the patient will find the mass at the top of the foot. The patient may have a burning sensation due to nerve irritation or compression of the nerve. Sometimes, a ganglion cyst mass occurs in the tarsal tunnel area, causing tarsal tunnel syndrome. If this is the case and the pain and burning sensation is not resolved with 
conservative treatment, excision of the mass is probably the best option. The patient may have skin irritation, as well as difficulty in walking and wearing shoes. If the ganglion is pushing on a nerve and causing irritation, something surgical needs to be done, such as aspiration or removal. Usually, the patient’s symptoms become better after these treatments.
The physician will need to differentiate a ganglion cyst from plantar fibromatosis. Remember, ganglion cysts tend to occur at the top of the foot. Plantar fibromatosis occurs at the bottom of the foot. A ganglion cyst will transilluminate, while plantar fibromatosis will not.
Treatment
Treatment typically consists of observation, shoe modification, and aspiration/injection of steroids. Surgery is performed as the last resort.
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