Tags: Disease.
Carpometacarpal (CMC) osteoarthritis (OA) also known as trapeziometacarpal osteoarthritis or osteoarthritis at the base of the thumb is a degenerative joint disease affecting the first carpometacarpal joint (CMC1). This joint is formed by the trapezium bone of the wrist and the first metacarpal bone of the thumb. Because of its relative instability this joint is a frequent site for osteoarthritis.
