The most common type—osteoarthritis, or wear-and-tear arthritis—occurs commonly in the joint at the base of the thumb, where the thumb meets the wrist. This joint, called the carpometacarpal ...

The base of the thumb—called the carpometacarpal joint, or CMC—is a common site for arthritis. Osteoarthritis (OA) can develop in the thumb. This condition gradually occurs from joint wear and ...