THE UPPER LIMB 



381 



of the flexor longus pollicis, into two collateral digital arteries for 

 the sides of the thumb, which appear on either side of the long flexor 

 tendon, between the superficial head of the flexor brevis pollicis and 

 adductor obliquus pollicis. Their distribution is similar to that of 

 the other digital arteries. The arteria princeps pollicis may give 

 a branch to complete the superficial palmar arch. 



The arteria radialis indicis passes downwards along the outer 

 side of the second metacarpal bone, lying upon the abductor indicis 

 and under cover of the adductor obliquus, and adductor transversus, 



Anterior Radial Carpal 



Anterior Ulnar Carpal 



Ulnar Artery 



Radial Artery 



Superficial Volar 



Princeps 

 Pollicis 



,. Deep Branch of Ulnar 

 _ _ Recurrent Branches 



_ Deep Palmar Arch 

 ist Digital Artery 

 from Superficial 

 Palmar Arch 



Radialis Indicis' ' 



ist Palmar Interosseus 



4th Digital Artery from Superficial Palmar Arch 



Fig. 204. — The Radial Artery in the Palm (Deep Palmar Arch) 

 (after Spalteholz). 



pollicis, and it becomes the digital artery of the outer side of the 

 index finger. It may give a branch to complete the superficial 

 palmar arch. 



Branches of the Deep Palmar Arch. — ^The palmar interosseous 

 arteries, three in number, arise from the convexity of the arch, 

 and pass downwards over the second, third, and fourth inter- 

 osseous spaces. Near the clefts of the corresponding fingers, they 

 terminate by joining the three compound digital arteries of the 

 superficial palmar arch. The innermost palmar interosseous, as a 

 rule, gives off a communicating branch to join the single digital 



