What Is a Ganglion Cyst?

 A ganglion cyst is a sac filled with a jellylike fluid that originates from a tendon sheath or joint capsule. The word “ganglion” means “knot” and is used to describe the knot-like mass or lump that forms below the surface of the skin. Ganglion cysts are among the most common benign soft-tissue masses. Although they most often occur on the wrist, they also frequently develop on the foot – usually on the top, but elsewhere as well. Ganglion cysts vary in size, may get smaller and larger, and may even disappear completely, only to return later. Causes Although the exact cause of ganglion cysts is unknown, they may arise from trauma – whether a single event or repetitive micro-trauma. Symptoms A ganglion cyst is associated with one or more of the following symptoms: • A noticeable lump – often this is the only symptom experienced • Tingling or burning, if the cyst is touching a nerve • Dull pain or ache – which may cate the cyst is pressing against a tendon or joint