What Is A Ganglion Cyst?

Ganglion Cysts Project From Joints Like A Balloon On A Stalk

A ganglion cyst is a collection of fluid that grows out of tissues surrounding a joint. Including;

• Tendon sheaths
• Ligaments
• Joint lining…

This type of cyst grows a bit like a balloon on a stalk. Where the fluid inside the balloon is thick and slippery. Similar in consistency to that, which lubricates your joints. They may sound scary but a ganglion cyst is benign. Meaning they are not cancerous, and in most cases, harmless. Typically they do not require any treatment. Ganglion cysts vary in size, and often grow larger with increased activity of the relevant area. And conversely with relative rest, the “lump” will generally become smaller.

Not All Cysts Actually Require Treatment

It is suggested that up to half of all ganglion cysts will disappear on their own. Without any need for medical treatment. However if the cyst itself becomes painful, or interferes with daily, work or recreational function, people may seek treatment. As a physio it is always nice when our patients have consulted their GP prior to attending. To make sure the swelling is in fact a ganglion cyst, and not a symptom of some other type of disease process. A simple bulk billed ultrasound and/or X-ray of the area can frequently accurately diagnose the presence of a cyst and gauge any associated joint, soft tissue changes. This isn’t always necessary, but can make the decision making process easier. 

Common Locations In The Body Ganglion Cyst Occur

The most common location for a ganglion cyst is on the back of the wrist. However, ganglion cysts can develop in several of the joints including the underside of the wrist and joints in the hand, including the end joint of a finger, and at the base of a finger. They can also occur at the knees, ankles and feet.

What Are The Causes Of Ganglion Cysts?

The exact cause of ganglion cysts is not known. One theory is that they are the result of tiny tears in the lining of a tendon, or joint. From this lining, or sheath the ganglion cyst grows like a ball of fluid on a thin stalk. The small tears in the tendon membrane, or joint capsule allow the fluid contents to “squeeze out”. From which the cyst may project out like one large lump. Or as a collection of a number of smaller cysts attached to a single ‘stalk’ deeper down in the tendon, or joint cover.
Another theory is that the body responds to overuse, trauma, or injury by forming an internal ‘blister’. Adding fuel to this theory is cysts are common in athletes such as gymnasts, who are repeatedly applying compressive loads to their wrists.

Disclaimer: Sydney Physio Clinic provides this information as an educational service and is not intended to serve as medical advice. Anyone seeking specific advice or assistance on What Is A Ganglion Cyst? should consult his or her physiotherapist, general practitioner or sports medicine specialist.