London Sports Foot & Ankle Surgery


What is it?

A ganglion is a discrete swelling most commonly found on the top of the foot or side of the ankle. Their size may fluctuate and they are usually painless unless pressing on a nearby nerve. Generally, once of a sufficient size they become a nuisance with shoe-wear.

What is it caused by?

Ganglions are benign swellings arising from weakening and degeneration of tendon sheaths and joint capsules. They distend as they become filled with fluid and cellular debris, are usually soft in consistency but then later harden. They tend to be deeply tethered to underlying structures in the foot but their location is almost always either dorsally on the bridge of the foot or around the tendons and joint capsule of the ankle and hindfoot.


Ganglions do not usually cause pain but can do so if related to a nearby nerve in the foot. They may come and go and when large can interfere with footwear. They affect all age groups. Any swelling in the foot that begins to change in consistency rapidly or enlarges over a short period of time should prompt further consultation with a foot and ankle surgeon - There are a few lumps in the foot that can be confused with a simple ganglion-cyst.


Ganglions can occur in association with inflammatory joint disease and arthritis and therefore investigation with a combination of plain X-rays of the foot and ankle and soft tissue imaging with either ultrasound or MRI is most often needed.

In most cases, the radiologist performing or reporting-on the imaging study will offer a firm diagnosis if the swelling is “radiologically-determinate”. In rare cases, the diagnosis might remain uncertain and it might be necessary to perform a biopsy to allow histopathological confirmation of the diagnosis- this is where a part or all of the swelling is removed under anaesthetic and sent to the laboratory.

Non-Surgical Treatment

Many people have had ganglions for years and they do not ever seek treatment. The ganglion has been of a constant site, size and consistency without ever producing disabling symptoms.

Any increase in size, tenderness, skin changes such as puckering or tethering or inflammation should prompt at least a G.P. visit for onward referral to an orthopaedic foot and ankle surgeon.

Your surgeon, on occasion may elect to aspirate the contents of the ganglion after imaging in the clinic. This is often a fruitless exercise since the fluid in the ganglion has become too gelatinous to enable its removal through a hypodermic needle.

Surgical Treatment

Surgical treatment of ganglions that are symptomatic or concerning in any way is extremely common and beneficial as it allows absolute confirmation of the nature of the lump, confirming it as benign and also enables symptom resolution.

This type of surgery is carried-out as a day-case procedure either with a very short-acting general anaesthetic or a local anaesthetic block.