Movement of the hand is produced by a combination of muscles, which originate in the forearm and insert into the hand and wrist, and a few muscles that arise within the hand itself. The side to side movements of the hand are capable of the most delicate adjustments and occur in all movements that require delicate and fine regulation and control, such as writing or threading a needle. The fingers have no muscles at all, only strong ~ligaments~ attached to muscles in the hand and forearm. Each of the four fingers has two long flexor and extensor ~tendons~ which arise from muscles in the forearm. The thumb is also controlled by extensor and flexor ~tendons~.
