RADIAL ARTERY. 305 



passes between the two heads of the first dorsal in.' erosseous muscle, into 

 the palm of the hand. It then crosses the metacarpal bones to the ulnar 

 side of the hand, forming the deep palmar arch, and terminates by inoscu 

 iating with the superficial palmar arch. 



In the upper half of its course, the radial artery is situated between the 

 supinator longus muscle, by which it is overlapped superiorly, and the 

 pronator radii teres ; in the lower half, between the tendons of the supina- 

 tor longus and flexor carpi radialis. It rests in its course downwards, 

 upon the supinator brevis, pronator radii teres, radial origin of the flexor 

 sublimis, flexor longus pollicis, and pronator quadratus ; and is covered 

 in by the integument and fasciae. At the wrist it is situated in contact 

 with the dorsal carpal ligaments and beneath the extejisor tendons of the 

 thumb ; and, in the palm of the hand, beneath the flexor tendons. It is 

 accompanied by venaB comites throughout its course, and by its middle 

 third is in close relation with the radial nerve. 



Plan of the Relations of the Radial Jlrtery in the Fore-arm. 



In Front. 

 Deep fascia, 

 Supinator longus. 



Inner Side. 



Pronator radii teres, 

 Flexor carpi radialis. 



Radial artery. 



Outer side. 



Supinator longus, 

 Radial nerve (middl 

 third of its course). 



Behind. 



Supinator brevis, 

 Pronator radii teres, 

 Flexor sublimis digitorum, 

 Flexor longus pollicis. 

 Pronator quadratus, 

 Wrist joint. 



The Branches of the radial artery may be arranged into three groups, 

 corresponding with the three regions, the fore-arm, the wrist, and the 

 hand ; they are 



Fore-arm, \ ^current radial, 



\ Muscular. 



f Superficialis volae, 



I Carpalis anterior, 

 Wrist, <j Carpalis posterior, 



Metacarpalis, 



[ Dorsales pollicis. 



f Princeps pollicis, 



Hand \ ^ ac ^ a ^ s indicis, 



] Interossese, 

 [ Perforantes. 



The Recurrent branch is given off immediately below the elbow ; it as 

 cends in the space between the supinator longus and brachialis anticus 10 

 supply the joint, and inosculates with the terminal branches of the superior 

 profunda. This vessel gives off numerous muscular branches. 



The Muscular brandies are distributed to the muscles on the radial side 

 of the fore-arm. 



26* u 



