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ANATOMY AND PHYSIOLOGY 



running down along the medial border of the biceps muscle into the 

 forearm, to end in the palm (supplying the biceps and brachial 

 muscle, all of the flexors of the forearm except on the ulnar side, 

 and most of the thumb muscles) ; the radial nerve from the pos- 

 terior cord, running in its groove to the front of the lateral epicon- 

 dyle, and dividing into the deep and superficial branches of the radial 

 nerve. By the radial and its deep branch all of the posterior mus- 

 cles of the arm and forearm are supplied. 



Nerves of the skin of the hand. Front of the thumb, index, 

 middle, and one-half of the ring finger, the median nerve. Back of 

 thumb, index, middle, and one-half of ring finger, the superficial 



FIG. 185. DORSAL SURFACE OF LEFT 

 HAND. (Morris.) 



FIG. 1 86. AN INTERCOSTAL NERVE 

 (Holden.) 



branch of the radial nerve. Both front and back of little finger and 

 one-half of ring finger, the ulnar nerve. 



Points of interest. The ulnar nerve, in the arm, is with the inferior pro- 

 funda artery and passes behind the medial epicondyle (it may be easily felt in 

 the groove behind the epicondyle, where pressure causes a sensation of pain 

 and tingling as far as the little finger). In the forearm it is on the ulnar side 

 of the ulnar artery and they pass in front of the wrist. 



The median nerve, in the arm, is with the biceps muscle and brachial 

 artery, and they pass in front of the elbow; in the forearm, it lies between the 

 deep and superficial muscles and passes with their tendons in Jronl of the 

 wrist. 



The radial nerve, in the arm, lies in the groove for the radial nerve be- 

 tween two heads the triceps muscle, with the superior profunda artery, and 

 comes to the front of the elbow. 



Its superficial branch, in the forearm, is on the radial side of the radial 

 artery; it winds around behind the wrist-joint. 



