652 THE VASCULAR SYSTEMS 



Branches (Figs. 464 and 465). The branches of the ulnar artery may b 

 arranged in the following groups: 



Anterior ulnar recurrent. 

 Posterior ulnar recurrent. 

 Forearm 4 n f Anterior interosseous. 



Interosseous | Posterior i nterosse o U s. 



I Muscular. 



w . ( Anterior ulnar carpal. 

 \ Posterior ulnar carpal. 

 u , J Profunda. 



1 \ Superficial palmar arch. 



The anterior ulnar recurrent (a. recurrentes ulnaris anterior) (Fig. 464) arises iin 

 mediately below the elbow-joint, passes upward and inward between the Brachiali 

 anticus and Pronator teres, supplies twigs to those muscles, and, in front of th 

 inner condyle, anastomoses with the anastomotica magna and inferior profunda 



The posterior ulnar recurrent (a. recurrentes ulnaris posterior} (Figs. 464 am 

 465) is much larger, and arises somewhat lower than the preceding. It passe 

 backward and inward, beneath the Flexor sublimis, and ascends behind the inne 

 condyle of the humerus. In the interval between this process and the olecranoi 

 it lies beneath the Flexor carpi ulnaris, and ascending between the heads of tha 

 muscle, in relation with the ulnar nerve; it supplies the neighboring muscles an< 

 joint, and anastomoses with the inferior profunda, anastomotica magna, an< 

 interosseous recurrent arteries. 



The interosseous artery (a. interossea communis) (Fig. 464) is a short trunl 

 about half an inch in length, and of considerable size, which arises immediately 

 below the tuberosity of the radius, and, passing backward to the upper border o 

 the interosseous membrane, divides into two branches, the anterior and posterio 

 interosseous. 



The anterior interosseous (a. interossea volaris) (Fig. 464) passes down the fore 

 arm on the anterior surface of the interosseous membrane, to which it is connectec 

 by a thin aponeurotic arch. It is accompanied by the interosseous branch of th< 

 median nerve, and overlapped by the contiguous margins of the Flexor profundu: 

 digitorum and Flexor longus pollicis muscles, giving off in this situation musculai 

 branches and the nutrient arteries of the radius and ulna. At the upper bordei 

 of the Pronator quadratus a branch, anterior communicating artery, descend; 

 beneath the muscle to anastomose in front of the carpus with the anterior carpa 

 arch. The continuation of the artery passes behind the Pronator quadratus, and 

 piercing the interosseous membrane, reaches the back of the forearm, and anasto- 

 moses with the posterior interosseous artery (Fig. 465). It then descends to the 

 back of the wrist to join the posterior carpal arch. The anterior interosseous gives 

 off a long, slender branch, the comes nervi mediana artery (a. mediana), which 

 accompanies the median nerve and gives branches to its substance. This artery 

 is sometimes much enlarged, and accompanies the nerve into the palm of the hand. 



The posterior interosseous artery (a. interossea dorsales) (Figs. 464 and 465] 

 passes backward through the interval between the oblique ligament and the 

 upper border of the interosseous membrane. It appears between the contiguous 

 borders of the Supinator [brevis] and the Extensor ossis metacarpi pollicis, and 

 runs down the back part of the forearm, between the superficial and deep layer 

 of muscles, to both of which it distributes branches (Fig. 465). Where it lies 

 upon the Extensor ossis metacarpi pollicis and the Extensor brevis pollicis, it is 

 accompanied by the posterior interosseous nerve. At the lower part of the forearm 

 it anastomoses with the termination of the anterior interosseous artery and with 

 the posterior carpal arch. Then, continuing- its course over the head of the ulna, 



