FOREARM AND HAND 119 



Each common volar digital artery, at the point at which 

 it divides, is joined by the corresponding volar metacarpal 

 artery from the deep volar arch. The proper volar digital 

 arteries give a liberal supply of twigs to the integument, 

 the sheaths of the tendons, and the joints of the fingers. 



Nervus Medianus (Median Nerve). The median nerve 

 enters the palm by passing deep to the transverse carpal liga- 

 ment with the flexor tendons. In this part of its course it is 

 overlapped by the mucous sheath which is wrapped around 

 the tendons. Further, before it emerges it assumes a flattened 

 form, and divides into two portions. Of these, the lateral 

 division is slightly the smaller of the two, and gives off 

 (i) a stout short branch to some of the intrinsic muscles of 

 the thumb; (2) three digital branches which go to the two 

 sides qf the thumb and the lateral side of the index finger. 



The muscular branch takes origin at the distal border of 

 the transverse carpal ligament, and at once turns laterally to 

 supply the abductor pollicis, the superficial head of the flexor 

 pollicis brevis, and the opponens pollicis. 



The proper volar digital nerves which run along the medial 

 side of the thumb, and the lateral side of the index, give 

 several branches to the fold of integument which stretches 

 between the roots of these digits ; whilst the proper volar 

 digital branch to the lateral border of the index gives a 

 minute twig to the first or most lateral lumbrical muscle. 



The larger medial division of the median nerve divides 

 into two branches. Of these one runs towards the cleft 

 between the index and middle fingers, and splits into the 

 proper volar digital nerves for the adjacent sides of those 

 digits. From this nerve a twig to the second lumbrical 

 muscle is given off. The second common volar digital branch 

 of the medial division of the median proceeds towards the 

 cleft between the middle and ring fingers, and divides into 

 the proper volar digital branches for their contiguous 

 margins. In some instances the latter nerve supplies 

 a twig to the third lumbrical muscle. 



In the palm the digital branches of the median proceed 

 distally deep to the superficial volar arch, but as they 

 approach the fingers they come to lie volar to the common 

 volar digital arteries, which in many cases may be observed 

 to pass through, or perforate, the nerves. As the proper 

 volar digital nerves lie upon the sides of the fingers, numerous 

 i 8c 



