WHAT ARE GANGLIONS?
A ganglion is a fluid-filler swelling of the lining of a joint or tendon. Although ganglions can form on any part of the foot, they most often appear on the ankle or top of the foot. Ganglions tend to change in size and usually grow slowly.

CAUSES
Repeated irritation can weaken the lining of a joint or tendon and lead to ganglions. People who ear boots are more vulnerable to ganglions, as this type of footwear puts stress on the foot and ankle. Bone spurs (bony outgrowths) may also cause ganglions by irritating the joints and tendons.

SYMPTOMS
Ganglions often form with no symptoms. But if the ganglion puts pressure on the nerves in the overlying skin it can cause tingling, numbness, or pain. Ganglions sometimes swell and their size can change with different activities or a change in weather.