By John C. Wolf, D.O.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

"NON-TEXTBOOK ANATOMY" LIKELY CAUSE OF WRIST PAIN, GANGLION CYST

Question: I am a 29 year-old woman, and I have had this annoying problem since childhood. I have difficulty doing any activity that puts pressure on my wrists, that is, any activity that bends my hands back with any degree of exertion. When I do this, I get pain in the back of my hands and it also shoots up my arms, but not all the way to my elbows. The pain can be quite severe, making just moving my hands up and down unbearable. On other occasions it is just uncomfortable. As an adult I have had ganglion cysts of the wrists occasionally. I've read about carpal tunnel syndrome, which doesn't seem to match my symptoms. What could be causing my wrist pain?

Answer: The wrist is a complicated mechanical structure. It involves the two lower arm bones, eight wrist bones called carpal bones, four fingers and the thumb. All of these parts move in relationship to one another. They are all held together by the collective work of many individual ligaments, muscles and joint capsules. This complex arrangement maximizes movement that allows us to do amazing things with our hands. Unfortunately, mechanical stability is sacrificed to some degree to accomplish this flexibility.
Each of the bony joints in the hands and wrist has a soft tissue lining that produces a lubricating synovial fluid. The tendons that move the fingers, hand and wrist slide back and forth over the wrist structures. These tendons run through sheaths that produce a lubricating synovial fluid too. So, all of this directly relates to your complaint because a ganglion cyst is a sack-like bulging that originates from a joint or a tendon sheath and becomes filled with synovial fluid.
The hands and wrists are common sites for ganglion cysts because of the large number of joints there. You see, ganglion cysts are believed to be a degenerative process of a synovial lining that occurs as a consequence of repeated traumas. As the cyst develops, the fluid within it stretches the tissue to form a "bump." The description of a cyst may cause a reader who has never had one of these to assume that the cyst is a soft fleshy bump. Not so! In fact, from the feel of a cyst it is sometimes difficult to determine if it is a solid tumor or not.
The firm cyst can push upon adjacent tissue and, thereby, cause pain. In the wrist it can even cause enough pressure to cause damage to bone.
I think the wrist pain you have experienced since childhood is the consequence of the way your wrists are made. Unfortunately, not everyone is put together in exactly the fashion that is illustrated in my anatomy book. Some individuals have wrist bone joints that are less mechanically stable than others. I think you are one of these people with "non-textbook" anatomy. Because of your bone and ligament structure, activities that many people perform without difficulty cause your wrist bones to slip and slide around more than is ideal. This produces painful stretching of supporting ligaments and or pinching of the synovial lining of involved joints. This would explain the episodes of hand, wrist and arm pain you have experienced.
One potential long-term consequence of having many episodes of this type of injury, what we doctors call repeated microtrauma, is sustaining sufficient cumulative injury to bring about a ganglion cyst.
So what should you do? First you need to see your doctor to determine if my guess is an accurate diagnosis of your condition. If so, he or she will probably recommend exercises to keep the muscles that move the wrist and hand in top condition along with avoidance of activities that you know will hurt you. Most ganglion cysts need no treatment. However, particularly large or painful ones may require injection or surgical removal to stop the pain. Your family doctor or an orthopedic surgeon can advise you about your choice for having optimal pain-free wrist function.

"Family Medicine" is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701. Past columns are available online at http://www.FamilyMedicineNews.org.