RADIAL AND ULNAR ARTERIES 



193 



Axillary artery 



Lateral cord 



Pectoral 

 muscle 



Median nerve 

 Brachial artery 



The radial and the ulnar arteries pass downward in the radial 

 and ulnar sides of the fore- 

 arm to the hands. The radial 

 supplies the muscles in front 

 of the radius, and winds to 

 the back of the wrist to find 

 its way to the palm by pass- 

 ing forward between the first 

 two metacarpal bones. It 

 forms the deep palmar arch, 

 which crosses the palm under 

 the long tendons (Fig. 130). 



The ulnar supplies the 

 muscles in front of the ulna, 

 and forms the superficial pal- 

 mar arch, which crosses over 

 the long tendons in the palm 

 (Fig. 131). 



Note. The superficial arch 

 crosses the palm opposite the 

 level of the web of the thumb 

 when put "on the stretch." The 

 deep arch crosses about a finger- 

 width nearer the wrist. 



The digital arteries run in the 

 sides of the fingers; they are 

 branches of the superficial arch. 



Clinical note. The pulsation 

 of the radial artery is easily felt 

 above the wrist in front, next to 

 the tendon of the radial flexor of 

 the wrist. 



Surgical note. A direct com- 

 munication exists between the 

 deep and superficial arches, con- 

 sequently severe hemorrhage 

 easily occurs in the palm, since 

 blood will flow from radial and 

 ulnar arteries at one and the same 

 time, and it is sometimes neces- 

 sary to ligate both. 



Ulnar nerve and 



artery 



adial nerve and 

 artery 



Branches to hand 



FIG. 131. AXILLARY, BRACHIAL, RADIAL AND 

 ULNAR ARTERIES. SUPERFICIAL ARCH. 



