394 



ULNAR AND RADIAL ARTERIES. 



latter and the index finger. The thumb and the radial side of the index 

 finger are supplied from the radial arttry. 



Fig. 276. 



Fig. 276. SUPERFICIAL DISSECTION OF THE LOWER 

 PART OF THE FOREARM AND THE HANI>, SHOWING 

 THE RADIAL AND ULNAR ARTERIES, THE SUPER- 

 FICIAL PALMAR ARCH, AND THE ACCOMPANYING 

 NERVES (from R. Quaiu); 



a, placed on the deep fascia of the forearm, between 

 the tendons of the palniaris longus and flexor carpi 

 rudialis muscles ; b, points by a line crossing the 

 pisiform bone to the ulnar nerve ; c, points to the 

 styloid process of the radius and twigs of the radial 

 nerve ; 1, radial artery lying on the flexor longus 

 pollicis ; 1', the radial artery passing behind the 

 tendons of the extensor ossis metacarpi pollicis 

 and extensor prirai internodii pollicis ; 2, superh'cialis 

 voice branch piercing the short muscles of the thumb 

 and emerging below to join the superficial palmar 

 arch ; 3, external branch of the princeps pollicis ; 4, 

 radialis indicis ; a branch from the superficial arch is 

 set-n joining the internal branch of the princeps 

 pollicis ; 5, ulnar artery lying upon the flexor digi- 

 torum profundus ; 5', the same descending on the 

 anterior annular ligament to form the superficial 

 palmar arch ; 6, deep branch of the ulnar artery 

 passing between the abductor and flexor minimi 

 digit! to join the deep arch, accompanied by the deep 

 branch of the ulnar nerve ; 7, branch of the super- 

 ficial arch to the ulnar side of the little finger ; 8, 

 division of the common branch to the 4th and 5th 

 fingers ; 9, the same to the 3rd and 4th fingers ; 10, 

 the same to the 2nd aud 3rd fingers ; 7 and 8, are 

 accompanied by the digital branches of the ulnar 

 nerve, and 3, 4, 9, aud 10, by the branches of the 

 median nerve. 



The digital arteries are placed at first super- 

 ficially to the tendon?, and then lie between 



them, accompanied by the digital nerves as far as the clefts of the fingers, 

 where they are joined by the anterior iuterosseous arteries, branches of the 

 deep arch. On the sides of the fingers, each artery lies beneath the corre- 

 sponding nerve, and gives branches which supply the sheaths of the tendons 

 and the joints, some of them anastomosing across the front of the bones 

 with similar branches from the opposite side. At about the middle of the 

 last phalanx, the two branches for each finger converge and form an arch, 

 from which proceed numerous small offsets to supply the matrix of the nail 

 and all the structures at the tip of the finger. 



[The peculiarities observed in the branches of the superficial palmar arch will be 

 noticed after the description of the deep arteries of the hand.] 



RADIAL ARTERY. 



The radial artery appears by its direction to be the continuation of the 

 brachial, although it does not equal the ulnar in size. It extends along the 

 front of the forearm as far as the lower end of the radius, below which it 



