[TA] anterior portion of the space enclosed by the brachial fascia, separated from the posterior compartment by the humerus and the lateral and medial intermuscular septa that extend from it; contains muscles that produce flexion, all innervated by the musculocutaneous nerve. SYN: compartimentum brachii anterius [TA], compartimentum brachii flexorum [TA], flexor compartment of arm*.