448 



THE ARTERIES OF THE UPPER LIMB. 



of the brachial opposite the neck of the radius, descends with a nearly straight 

 course, along the outer part of the front of the forearm, to the styloid process 

 of the radius. Its position is indicated by a line drawn from the middle of the 

 bend of the elbow to the narrow interval between the scaphoid bone and the tendons 

 of the extensors of the thumb, which can be readily felt on the outer border of the 

 wrist. 



The radial artery is nearer to the surface than the uluar ; it is covered in its 

 upper half by the fleshy part of the supinator longus muscle, which must be drawn 



Fig. 366. DEEP ANTERIOR VIEW OF THE ARTERIES OF THE 

 FOREARM AND HAND. (Tiedemann.) ^ 



For the full description of this figure, see p. 444. The fol- 

 lowing numbers refer to the radial artery and its branches : 5, 

 upper part of the radial artery and radial recurrent ; 5', lower 

 part of the radial artery, giving off the anterior carpal and 

 superficial volar branches ; 5", the radial artery, emerging 

 from between the heads of the abductor indicis muscle and 

 forming the deep palmar arch ; 9, placed between the princeps 

 pollicis and radialis indicis branches of the radial artery. 



aside in order to bring the vessel into view, in its 

 lower half, only by the integument and fascia. At 

 first it is in contact with the tendon of the biceps, 

 and is supported by the fatty tissue contained in 

 the hollow at the front of the elbow, which 

 separates it from the short supinator muscle. It 

 then rests in succession on the insertion of the 

 pronator teres, the thin radial origin of the flexor 

 sublimis, the flexor longus pollicis, the pronator 

 quadratus, and the lower end of the radius. It is 

 at this last point that the pulse is usually felt 

 during life. To the inner side of this vessel lie the 

 pronator teres in the upper part of its course, and 

 the flexor carpi radialis in the remainder ; and on 

 the outer side, in its whole course along the fore- 

 arm, is the supinator longus muscle. 



Relation to veins. The artery is accompanied 

 by venw comites, which have the usual arrangement 

 of those veins. 



Relation to nerves. The radial nerve is near the 

 artery, on its outer side, in the middle third of its 

 course. At the elbow this nerve is separated from 

 the artery by a considerable interval ; and towards 

 the lower end of the forearm it turns backwards 

 beneath the tendon of the supinator longus, to 

 reach the dorsal aspect of the limb, and thus loses 

 all connection with the artery. Some filaments of 



the external cutaneous nerve pierce the fascia to reach the lower part of the artery, 



which they accompany to the back of the carpus. 



BRANCHES. In the forearm the radial artery gives many small muscular offsets 



to the surrounding muscles and the following named branches, viz. : 



1. The radial recurrent artery, which varies much in size, arches upwards 



from the radial soon after its origin, running between the branches of the musculo- 



spiral nerve. It lies at first on the supinator brevis, and then on the brachialis 



