FRONT OF THE ARM 81 



and dissect out the radial nerve, with the anterior terminal branch of the 

 profunda brachii artery, which lie deeply in the interval between them. 

 Here also the anastomosis between the profunda brachii artery and the 

 radial recurrent arteries may be made out, in a well-injected subject ; 

 and the twigs which are given by the radial nerve to the brachialis, the 

 brachioradialis, and the extensor carpi radialis longus, should be looked 

 for. 



Fossa Cubitalis (O.T. Antecubital Fossa). This is a 

 slight hollow in front of the elbow-joint. It corresponds to 

 the fossa poplitea of the lower extremity, and within its area 

 the brachial artery divides into its two terminal branches. 

 In the first instance, consider the structures which cover it. 

 Some of these have already been removed, they are the skin, 

 superficial fascia, and deep fascia. Within the superficial 

 fascia are the median basilic and median cephalic veins, the 

 volar branch of the medial cutaneous nerve of the forearm 

 and the lateral cutaneous nerve of the forearm. These 

 structures constitute the coverings of the fossa. 



The fossa is triangular. Its base is directed proximally, 

 and is usually regarded as being formed by a line drawn 

 between the two epicondyles of the humerus. The medial 

 boundary is the pronator teres muscle, and the lateral boundary 

 the brachioradialis. The meeting of the two muscles distally 

 constitutes the apex of the fossa. The boundaries must first be 

 cleaned, then the contents of the fossa may be dissected. 



Within the fossa is the termination of the brachial artery 

 and the proximal parts of the radial and ulnar arteries, into 

 which it divides. To the lateral side of the main vessel 

 is placed the tendon of the biceps brachii, and to its 

 medial side the median nerve. A quantity of loose fat is 

 also present. The ulnar artery leaves the space by passing 

 under cover of the pronator teres ; the radial artery is 

 continued distally beyond the apex of the fossa, overlapped 

 by the brachioradialis. The median nerve disappears between 

 the two heads of the pronator teres, and the tendon of 

 the biceps brachii inclines posteriorly, between the two bones 

 of the forearm, to reach its insertion into the radial tuberosity. 



When the fatty tissue has been thoroughly removed the 

 floor of the space will be revealed. This is formed by the 

 brachialis and the supinator muscles. In this situation the 

 brachialis is closely applied to the anterior aspect of the 

 elbow-joint, whilst the supinator is wrapped round the upper 

 part of the radius. 



VOL. i 6 



