Wrist joint is second most active joint after ankle joint. Wrist joint is a perfect geometrical pattern that matches convex shape of carpal bones with concave articulating surface of radius. Ulnar bone is not in contact with carpal bone at rest, but during supination and pronation, the carpal bone gets linked to ulna to optimize the rotation.
During motion of the wrist, such as flexion and extension, this network of bones and ligaments moves in synchrony. The presence of small joints within the wrist joint actually gives the wrist joint a wide range of motion. The hand can thus move sideways, turn or rotate, bend up and down. The motion also occurs in a smooth succession that is often likened to a concertina