THE BRACHIAL ARTERY 



575 



A line drawn from the groove medial to the coraco-brachialis and biceps muscles 

 to midway between the epicondyles of the humerus will indicate its course. It 

 is accompanied by two veins which frequently communicate across the arter}'. 

 In addition to the branches named below the brachial artery gives off numerous 

 muscular branches and, occasionally, the nutrient artery to the humerus. The 

 muscular branches usually come off from the lateral side of the artery; one in 

 particular, which supplies the biceps muscle, is frequently of large size. 



Relations. — In front, the artery is covered by the integument and superficial and deep 

 fasciae, and at the bend of the elbow by the lacertus fibrosus of the biceps, and in muscular 

 subjects by the overlapping margins of the brachio-radiaUs and pronator teres. In the middle 

 third of the arm it is crossed obliquely from the lateral to the medial side by the median nerve, 

 and at the bend of the elbow bj^ the median cubital vein, the bicipital fascia intervening (fig. 475). 



Behind, it lies successively on the long head of the triceps (from which it is separated by 

 the radial (musculo-spiral) nerve and profunda artery), on the medial head of the triceps, 

 on the insertion of the coraco-brachiaUs, and thence to its bifurcation on the brachiahs muscle. 



Fig. 469. — The Brachial, Artery at the Bend of the Elbow, Left Side, Front View. 

 (From a mounted specimen in the Anatomical Department of Trinitj' College, Dublin.) 



Posterior branch of medial 



antibrachial cutaneous 



nerve 

 Anterior branch of medial 



antibrachial cutaneous 



serve 



Biceps muscle 



Brachial artery 



Branch to pronator teres 

 Lacertus fibrosus, cut 



Pronator teres muscle 



Median nerve 



Ulnar artery 



Branch of radial nerve to 

 brachio-radialis 



Superficial radial nerve 



Radial recurrent artery and 

 deep radial nerve 



Tendon of biceps 

 — Musculo-cutaneous nerve 



Brachio-radialis muscle 



* Radial artery 



Lateral to the artery is the coraco-brachiaHs above, and the muscular belly of the biceps 

 below, both of which shghtly overlap the vessel, and at the bend of the elbow the tendon of 

 the biceps. The lateral vena comitans is also to its lateral side. The median nerve is in close 

 contact with the lateral side of the artery in the upper third of its course, but in the middle third 

 crosses the artery obhquely to gain the medial side. 



Medial to the artery in the upper part of its course are the medial antibrachial (internal) 

 cutaneous and the ulnar nerves; the latter nerve, however, leaves the artery about the origin 

 of the ulnar collateral (inferior profunda) branch, to make, with that vessel, for the medial 

 epicqndyle. Lower down, the medial antibrachial cutaneous nerve also leaves the artery, 

 by piercing the deep fascia. The median nerve is in close contact with the medial side of the 

 artery in its lower third and at the bend of the elbow. The basihc vein is superficial to it, 

 and a httle to its medial side in the greater part of its course, but separated from it by the deep 

 fascia. The medial vena comitans runs along its medial side. 



Branches of the Brachial Artery 



The branches of the brachial artery are: — (1) The profunda brachii; (2) the 

 superior ulnar collateral (inferior profunda); (3) the inferior ulnar collateral 



