A ganglion cyst is a round, fluid-filled mass that forms on or near a joint or tendon. It is non-cancerous and typically harmless. Most commonly found on the wrist or hand, it can also develop at the ankle or foot. The exact reason why ganglion cysts form in some people and not others remains unclear.
Many ganglion cysts cause no symptoms at all and can be safely left alone. Others press on a nearby nerve, causing pain, tingling, numbness or a noticeable loss of mobility. When a cyst is on the foot or ankle, it can cause discomfort during walking or wearing shoes. In these cases, treatment is warranted.
Non-surgical aspiration (draining the cyst with a syringe) is an option, but carries a high rate of recurrence. Surgical removal of the cyst and its root stalk is the most effective treatment and carries the lowest risk of the cyst returning. The surrounding nerves and vessels are carefully protected throughout, leaving only a small scar at the site.