Wrist ganglia are benign tumors which are linked to an anomaly in the capsule (ligament tissue which surrounds the wrist bones). Dorsal ganglia, located on the back of the hand, are the most frequent type of synovial cysts. Palmar ganglia, located near the radial artery, are the second most frequent. Fairly often, degenerative microcysts appear near the initial ones.
There are no known predisposing factors.
Most often, the cause for the occurence of a ganglion is unknown. However, in some cases, it is possible to observe a post-traumatic onset of synovial cysts. In such cases, one should check for associated ligament lesions.
The evolution of ganglia, whether dorsal or palmar, is very particular. Very often, they appear during a specific period and then tend to completely disappear. They are seldom painful. However, in some cases, the excess in internal pressure may lead to pain. Occasionally, their disappearance may take several months. When they remain, depending on their size, the discomfort they generate may be only esthetic or, at times, functional by limiting the wrist range of motion and decreasing the muscle strength.
Simple AP and lateral view X-rays of the wrist bones can help determine whether there any traumatic lesions related to the cyst (such as fractures, scapholunate dissociation, arthritis…). When the actual localization of the cyst is unclear, the physician can request an MRI (Magnetic Resonance Imaging). This completely harmless medical exam explores soft tissue and will help determine the exact cause of the cyst.
A number of treatment methods have been put forward, from abstention to open surgery.
Medical Treatment
Most often, ganglia are benign tumors without consequences (except cases where the cyst is related to a traumatic lesion). As such, patients generally wish to remove them for cosmetic reasons. Then a medical treatment may be indicated.
The treatment may involve a simple injection or percutaneous needle evacuation of the ganglion, knowing that recurrence is almost certain in a majority of cases. The method consisting in crushing the cyst with a coin, as put forth by some of our former colleagues, is both painful and ineffective.
Surgical Treatment
There are two types of surgical treatment:
– “Open” surgical treatment, which consists in a normal procedure during which the surgeon incises the skin, then dissects the ganglion down to its origin and removes it with part of the joint capsule which is responsible for the cyst. Dorsal ganglia are less risky to operate on than palmar ganglia, as the latter are located near the radial artery.
– Arthroscopic treatment, which is a simpler technique for the patients. Through two small openings the size of which does not exceed 2 millimeters, and do not require stitches, the surgeon uses a camera to look inside the wrist join and find the cyst’s origin. Thanks to miniature instruments, the surgeon may then remove the cyst’s origin, the adjacent capsule, and the cyst wall. Patients can use their hands immediately after surgery. There are no stitches which need to be removed. This technique can also be performed for anterior ganglia as the cyst removal process takes place away from the radial artery, therefore decreasing the risk of damaging it.