|Cyst on left wrist|
A ganglion cyst (also known as a bible bump) is a swelling that often appears on or around joints and tendons in the hand (or sometimes feet). The size of the cyst can vary over time, often becoming more inflamed if irritated. It is most frequently located around the wrist and on the fingers.
The exact cause of the formation of ganglion cysts is still unknown but they are thought to be due to a degeneration of the fibrous tissue surrounding joints leading to a cystic structure1,2. For this reason they are often found around joints, especially the wrist joint (the location of 90% of ganglions2). They are not due to pockets of the synovium protruding from the joint capsule, a common misconception. They occur most often in the 20–60 age group and are three times more common in females1. They are benign but need to be differentiated from more serious conditions. They contain clear fluid similar to synovial fluid (a clear, lubricating, viscous fluid found in the synovial cavity of joints).
They are not generally considered harmful and are normally asymptomatic. Sometimes they may cause limitations of movement and can also cause weakness, pain and paraesthesia (pins and needles) if they press on adjacent nerves.
Frequently, the cysts will disappear over time, so in cases of small cysts that do not cause other symptoms, no therapy is necessary.
If a ganglion cyst is symptomatic, it can be managed by aspiration or excision. Aspiration of the cyst is the simpler method, but cysts will develop again in about 50% of cases. Recurrence rate after surgery is only 5–10%; the procedure is simple, and usually there are no complications. Recurrence rates are lower when the hand or finger is immobilized for 1–2 weeks. Arthroscopy of the wrist is becoming a viable alternative to open excision of ganglion cysts. during arthroscopy the origin of the cyst can be seen. no immobilization is needed after arthroscopy.
One traditional method of treating a ganglion cyst was to strike the lump with a large, heavy book, causing the cyst to rupture and drain into the surrounding tissues. Since even the poorest households usually possessed a Bible, that was what they used, which is how ganglion cysts came to be nicknamed "Bible Bumps" or sometimes "Gideon's Disease." This method of treatment is no longer recommended as patients risk damage to the surrounding area.
1. http://www.emedicine.com/orthoped/topic493.htm 2. Browse NL (1997) Symptoms and Signs of Surgical Disease. 3rd ed. London: Arnold.