Wrist Flexion and Extension

Flexion at the wrist might also be called flexion of the hand, but it usually isn't.

Muscles: all of the flexor muscles crossing the wrist joint, but especially the flexor carpi radialis and flexor carpi ulnaris.

Extension at the wrist might also be called extension of the hand, but it usually isn't.

Muscles: all of the extensor muscles that cross the wrist joint, but especially the extensor carpi radialis longus and brevis and the extensor carpi ulnaris.