One of the most common problems that I see in the office involves joint pain from arthritis in the thumb. One of the reasons that’s so common is because anytime you use your hand, you’re using your thumb. And the specific biomechanics of the thumb are that if you pinch a pound out here at the tip, it’s 12 pounds of pressure at the base of the thumb. You have multiple joints in the thumb…the carpometacarpal joint is really the joint that sees the most stress.
There are basically three treatment options for the management of thumb arthritis. The first is a brace…a special brace that the therapist makes for you. We’ll usually send someone to the hand therapist, and they’ll make a custom brace. I’ll have the patient wear that for about four weeks and come back and see me. If the joint pain is not any better, then we’ll frequently try a cortisone injection, which about 80 percent of people find is effective. About 70 percent of people will feel better just from wearing the brace, so only 20 to 30 percent need the injection. The injection works about 80 percent of the time. The last option for treatment is hand surgery, and that’s what we call a CMC Arthroplasty.
The procedure itself involves a small incision directly over the top of the thumb joint. The source of the joint pain is arthritis, which is a breakdown of the cartilage between two bones, is occurring between this bone which we call your metacarpal and the little small wrist bone called your trapezium. That cartilage surface is worn out. Through a small incision, which is about an inch long, we go down and actually remove the trapezium bone to remove that bone rubbing on bone. Then we’ll make a small incision in your forearm, and we’ll actually use one of your forearm tendons that you can functionally do without to fill that space. It’s not any more complicated than taking that tendon and rolling it up in a big ball and putting it in the hole. It serves as a spacer – a soft spacer, a sort of Oreo…you know the middle of the oreo there – between the bones, so you’re not getting any bone rubbing on bone and experiencing thumb joint pain.
Once you are out of your six-week splinting period, your activities are really just based on comfort. Most people will continue to use the splint for a period of weeks as they’re starting into their physical therapy program, but really they’re allowed to do whatever feels comfortable.
A lot of people have this concept that if its arthritis you can’t do anything about thumb joint pain, and that is absolutely not true, particularly for this thumb joint. We have several options that really can significantly help someone with overall hand function. If your thumb is working better, your whole hand is going to work better.