THE FRONT OF THE ARM 101 



coraco-brachialis, and brachialis. A little distal to the middle 

 of the arm, on the medial side of the artery, seek for its nutrient 

 branch to the humerus. Clean the superior profunda branch, 

 which accompanies the radial nerve, and the superior ulnar 

 collateral branch which accompanies the ulnar nerve. About 

 two inches proximal to the elbow, find the inferior ulnar 

 collateral branch, follow it towards the medial intermuscular 

 septum, and note its division into two branches, an anterior 

 which descends in the front of the medial epicondyle to anasto- 

 mose with the volar ulnar recurrent, and a posterior which 

 pierces the medial intermuscular septum. Lastly, clean the 

 brachial artery itself. 



Nervus Medianus. The median nerve arises in the axilla 

 by two heads, one from the medial and one from the lateral 

 cord of the brachial plexus. The medial head crosses the 

 front of the axillary artery to unite with the lateral head. 

 The nerve thus formed descends, along the lateral side of 

 the distal part of the axillary artery and the proximal half of 

 the brachial artery, to the level of the insertion of the coraco- 

 brachialis; there it crosses in front of the brachial artery 

 (sometimes behind) and descends along its medial side to 

 the bend of the elbow. It gives off no branches either in 

 the axilla or in the arm. 



Nervus Ulnaris. The ulnar nerve is the largest branch 

 of the medial cord of the brachial plexus. It descends, along 

 the medial sides of the third part of the axillary artery and 

 of the proximal half of the brachial artery, to the insertion of 

 the coraco-brachialis ; then it leaves the brachial artery and, 

 accompanied by the superior ulnar collateral artery, passes 

 distally and backwards through the medial intermuscular 

 septum, into the posterior compartment. In the posterior 

 compartment it descends, along the medial head of the triceps, 

 to the back of the medial epicondyle. Do not follow it into 

 the posterior compartment at present ; it will be dissected 

 there at a later period. Like the median nerve it gives 

 off no branches whilst it is in the axilla and the arm. 

 Accompanying the ulnar nerve will be found the ulnar 

 collateral branch of the radial nerve which descends to 

 the distal part of the medial head of the triceps. 



Arteria Brachialis. The brachial artery is the direct con- 

 tinuation of the axillary artery; it begins, therefore, at the lower 

 border of the teres major, and it passes, distally and slightly 

 laterally, to the cubital fossa, where, at the level of the neck of 

 the radius, it divides into its two terminal branches the radial 



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