The wrist is a complex joint that connects the hand to the forearm. It is formed by the two bones of the forearm—the radius and the ulna—and eight small carpal bones. The carpal bones are arranged in two rows at the base of the hand. There are four bones in each row.
The joint surface of each bone is covered with articular cartilage—a slippery substance that protects and cushions the bones as you move your hand and wrist.