In the wrist joint and finger joints, or more rarely in other joints, nodes can occasionally develop that cause pain on movement or pressure. They are caused by swelling of the joint mucosa and are so full of joint fluid that they feel like they are made from bone.
The medical term for this benign tumour is ganglion.
Often, pain is experienced when the ganglion is touched or when the affected area is moved. In some cases, if the ganglion is pressing on a nerve, there may be sensation disturbances, such as numbness or tingling.
It is rare for a ganglion to resolve by itself. If it doesn't, there are a variety of treatment options available. In the context of conservative therapies, drainage and injections are used. If these measures fail to achieve a permanent resolution of the problem, surgical removal can be carried out under local anaesthetics.
You will find a detailed description of the procedure under Hand surgery.