A ganglion is a round cystic swelling that develops on the back of a patient's wrist, or less commonly on the dorsum of his foot, usually in connection with a tendon sheath, or a joint capsule. Flex his wrist over your knee; this will usually make the fluid in the cyst tense. Bang the tense cyst with a large object, such as a heavy book. It will usually disperse the fluid. If it fails, repeat it under general anaesthesia using a rubber mallet, or a similar object. The chances of it recurring are not much higher than those following surgery. Avoid operating if you can, and only do so on the indications below. If you fail to remove a ganglion completely, it is more likely to recur, and if you dissect too energetically, you may damage a tendon.

REMOVING A GANGLION INDICATIONS. A ganglion which causes pain, or is large and unsightly, and which has recurred twice after rupture, or could not be ruptured.

ANAESTHESIA. An axillary block, an intravenous forearm block, or general anaesthesia.

METHOD. Apply a tourniquet (3.9). Incise transversely in the line of the skin crease over the ganglion. Dissect out the cyst without damaging tendons, nerves, or vessels. Try not to rupture it, because this will make removing all its extensions more difficult. Excise it, and a short length of the tendon sheath from which it arises (leaving the tendon naked is unimportant). If you fail to do this, it is more likely to recur, which it may do anyway.

Let down the tourniquet, control bleeding, sew up the skin with 2/0 or 3/0 monofilament, and apply a pressure dressing for 24 hours.