THE RADIAL ARTERY. 



449 



Fig. 367. ARTERIES OF THE OUTER AND BACK PART OP THE 

 ARM AND HAND, SUPERFICIAL VIEW. (Tiedemann.) 



a, deltoid muscle ; 6, outer head of triceps ; c, biceps ; d, 

 brachialis anticus ; e, supinator longus ; /, ext. carpi radialis 

 longior ; g, brevior ; h, ext. communis digitorum and minimi 

 digiti ; ?', ext. carpi ulnaris ; k, anconeus ; I, flexor carpi 

 ulnavis ; m, ext. ossis metacarpi pollicis ; n, ext. brevis pol- 

 licis ; o, ext. longus pollicis ; 1, 1, cutaneous and posterior 

 terminal branches of the superior profunda artery, the latter 

 descending to anastomose with the branches of the interosseous 

 and radial recurrent arteries ; 2, above the posterior annular 

 ligament, the anterior interosseous artery ; 3, posterior carpal 

 branch of the ulnar artery ; 4, radial artery, taking its course 

 between the external lateral ligament of the wrist- joint and 

 the tendons of the extensor muscles before passing near 5, 

 between the two heads of the abductor indicis ; beneath the 

 extensor tendons is seen the posterior carpal arch, giving in 

 this case the three dorsal interosseous arteries ; 6, the inner 

 dorsal artery of the thumb ; 7, the outer dorsal artery of the 

 index finger ; 7', the metacarpal branch of the ulnar artery, 

 and between 7, and 7'. the remaining dorsal digital arteries, 

 formed by the bifurcation of the dorsal interosseous arteries. 



anticus, being covered by the supinator longus. 

 In the interval between the last two muscles, it 

 anastomoses with the anterior terminal branch of 

 the superior profunda. 



From the lower or convex side of this artery are 

 given off several branches ; one or more, of con- 

 siderable size, to the supinator and radial extensor 

 muscles, and some beneath the latter to anastomose 

 with the posterior interosseous recurrent. It also 

 supplies the supinator brevis and brachialis anticus 

 in part. 



2. The anterior radial carpal is a small 

 branch which arises near the lower border of the 

 pronator quadratus muscle, and runs inwards in 

 front of the wrist to anastomose with a similar 

 branch of the ulnar artery. The arch thus formed 

 (anterior carpal arch) is joined above by communi- 

 cating offsets from the anterior interosseous artery, 

 and below by the recurrent} branches of the deep 

 palmar arch, thus giving rise to a network over 

 the front of the wrist, from which twigs are sup- 

 plied to the carpal bones and articulations. 



3. The superficial volar artery, arising 

 from the radial near the place where it leaves 

 the front of the forearm, passes onwards into the 

 hand. In size it is variable ; in most instances it 

 is small, and ends in the muscles of the thumb ; 

 but in others it attains considerable size, and 

 crossing these muscles, terminates by inoscula- 

 ting with the radial extremity of the superficial palmar arch, which it thus 

 completes. 



AT THE WRIST. Below the styloid process of the radius, the radial artery 

 turns backwards, passing beneath the tendons of the extensor ossis metacarpi and 

 extensor brevis pollicis, and resting upon the external lateral ligament of the wrist- 



