SHOULDER, ARM, FOREARM, AND HAND. 



165 



The Palmar Interossei Muscles (Figs. 114 and 115). These are three in 

 number. They are physiological adductors. They arise from one side of the 

 metacarpal bone corresponding to the finger, into the base of whose proximal 

 phalanx they are inserted. They are inserted into the bases of the proximal 

 phalanges of the index, little, and ring fingers in such a way as to adduct these 

 fingers to the middle finger. Trace branches to them from the deep palmar 

 branch of the ulnar nerve. 



The Deep Palmar Branch of the Ulnar Nerve. You have seen the ulnar 



Anterior inter osseous 



Radial artery 



Anterior radial carpal 



Superficial volar 



Posterior radial carval 

 Radial artery at wrist 



Dorsalis pollicia 



Metacarpal or 



first dorsal 



iiiterosseorts 



Pi-inceps pollici-s 



Dorsalis indicis 

 Radialis indicis 



Ulnar artery 



Anterior ulnar 

 carpal 



Posterior ulnar 

 carpal 



Deep ulnar 

 Superficial arch 



Carpal recurrent 



Posterior communi- 

 cating or perforat- 

 ing 



Palmar inlerosseous 



Second, third, and 

 fourth palmar 

 digital 



Second and third 

 dorsal interosseous 



First palmar digital 



A nterior communi- 

 cating or perforat- 

 ing 



First dorsal branch of collateral 

 digital 



Second dorsal branch of collateral 

 digital 



Anastomosis of collateral digital 

 arteries about matrix of nail 

 and pulp of finger 



FIG. 116. ANASTOMOSES AND DISTRIBUTION OF THE ARTERIES OF THE HAND. 



nerve crossing the anterior annular ligament, and dividing, below the pisiform 

 bone, into superficial and deep palmar branches. (Fig. in.) You traced the 

 superficial branches to the palmaris brevis, the skin over the hypothenar emi- 

 nence, and to the little finger and half the ring finger. (Fig. 1 1 1.) You will now 

 trace in review the deep palmar branch, between the abductor minimi digiti and 

 flexor brevis minimi digiti, and see it join company with the deep palmar arterial 

 arch, and send off branches to these muscles : 



