What is a Ganglion Cyst
A ganglion cyst is a mass of tissue filled with a jelly-like fluid. It appears as a bump, lump, or knot, usually on the top of the foot. They vary in size, sometimes getting bigger or smaller, sometimes disappearing entirely, and can return. 

Signs and Symptoms
A ganglion cyst can have one or more of the following symptoms:

• A noticeable lump
• Tingling or burning
• Dull pain or ache
• Difficulty wearing shoes due to them rubbing against the cyst, causing irritation. 

Causes of a Ganglion Cyst
Ganglion cysts are usually caused by some kind of injury. They may appear after dropping something heavy on the foot, twisting the foot while walking, or if too much stress was placed on a joint or tendon. Sometimes, the patient might not even remember the injury that caused the cyst.

Diagnosis
Ganglion cyst are fairly easy to diagnose; your podiatrist will perform a thorough examination of your foot, pressing on the bump, shining a light through it, and in some cases remove a small amount of fluid from the cyst for study.