The diagnosis is made by taking a thorough history of the clinical course of the condition. Physical exam will reveal a firm, rubbery mass that appears encapsulated and will have a discreet boundary. They tend to be firmly adhered to the underlying deep tissues under the skin. A x-ray will reveal the shadow of the soft tissue swelling. On occasion there may be a small bone spur in the area of the ganglion. Spurring indicates a level of arthritis in the joint near the ganglion. A MRI or CT scan will clearly define the mass but is not necessary to make the diagnosis. If a ganglion were suspected within the deep structures of the foot a MRI would be useful to identify the size and extent of the mass.
Small ganglions that are not symptomatic or painful usually require no treatment. A non-surgical form of treatment is termed "needling". This involves numbing the area with a local anesthesia. Once the area is numb a large gauge needle is placed into the ganglion. Aspiration of ganglion fluid is attempted, however, because of the thickness of the fluid it is often difficult to draw the fluid out. The ganglion is then punctured with the needle several times. A steroid medication may then be placed into the mass and a snug bandage applied. This treatment has a 70% recurrence rate. The definitive treatment for a ganglion is surgical excision. (See surgical excision of a ganglion)