Ganglion cysts are benign soft tissue tumors that most frequently occur around the dorsum of the wrist and on the fingers, although any joint can be affected. They can present as a swelling or as joint pain. Ganglion cysts are most common in patients aged 20-40 years but may affect any age group.

They usually present as cosmetic concerns but may uncommonly have associated neurologic or vascular symptoms. If the cyst compresses an underlying nerve, the patient may report distal numbness or weakness. Vascular compression may cause coolness or cyanosis of areas distal to the cyst. The size of the cyst may vary over time and can increase after activity.

Although the exact etiology is unknown, it is likely that a small tear forms in a joint capsule or tendon sheath, allowing extravasation of synovial fluid into the adjacent tissue. When the fluid reacts with local tissue, it becomes more gelatinous and a cyst wall forms. While it has been postulated that ganglion cysts are caused by chronic joint inflammation, this theory is less likely because inflammatory changes are not seen in ganglion cysts.

Related topic: ganglion cyst of wrist