Plate 53. Anterior region of the arm. First and second layers. Volume 1; Osteology, syndesmology, myology of Atlas d'anatomie descriptive du corps humain by Louis Constantin Bonamy and Paul Broca with illustrations by Emile Beau, 1844. The arm can be divided into the upper arm, which extends from the shoulder to the elbow, the forearm which extends from the elbow to the hand, and the hand. The arm is divided by a fascial layer separating the muscles into two osteofascial compartments: the anterior and the posterior compartments of the arm. The biceps (biceps brachii) is a large muscle that lies on the front of the upper arm between the shoulder and the elbow. The large deltoid muscle is considered to have part of its body in the anterior compartment. This muscle is the main abductor muscle of the upper limb and extends over the shoulder. The antebrachial fascia (antibrachial fascia or deep fascia of forearm) continuous above with the brachial fascia, is a dense, membranous investment, which forms a general sheath for the muscles in this region; it is attached, behind, to the olecranon and dorsal border of the ulna, and gives off from its deep surface numerous intermuscular septa, which enclose each muscle separately.