Thumb (CMC joint) Arthritis The carpometacarpal (CMC) joint is the most common site for arthritis in the hand.
We offer several braces to help stabilize this joint along with various modalities to help decrease swelling and pain.
In the most common form of arthritis, Osteoarthritis (OA) or Degenerative Joint Disease (DJD), the cartilage that covers and protects the joints, wears out. Without the protective cartilage, the bones in the joint grind against one another wearing the joint down and causing pain and instability.
As the disease progresses, the CMC joint may sublux (slip out of place), causing the thumb to collapse into the palm, forming a “Z” or zigzag deformity. This collapse deformity makes it difficult to open the thumb away from the palm and makes grasping and pinching progressively more difficult.
Pain at the base of the thumb where it joins the wrist is the most common symptom of CMC joint arthritis. Pain is most commonly felt when trying to pinch or grip something tightly or when holding onto something small like a pen or a key. Pressure that pushes down on the thumb may also cause pain that is often described as “grinding” pain.