The basic movements of the fingers include flexion, extension, adduction, and abduction. It should be noted that because of the positioning of the thumb, when it flexes, it moves toward the fingers. In finger flexion, the anterior (palm sides) of the fingers come closer together. In total finger flexion, as in making a fist, the anterior sides of the fingers move toward themselves and toward the palm of the hand.
In extension, the fingers straighten from a flexed position or move somewhat behind the back surface of the hand at the metacarpophalangeal joints. These actions are not used to a great extent in sports or daily activities. Their main role is to guide (control) finger movements and to balance finger flexor strength. It is also possible to see finger abduction and adduction at the metacarpophalangeal joint. In these actions the fingers are moved sideways.
