528 



THE ARTERIES 



Behind, it lies successively on the long head of the triceps (from which it is 

 separated by the musculo-spiral nerv^e and superior profunda artery), on the inner 

 head of the triceps, on the insertion of the coraco-brachialis, and thence to its 

 bifurcation on the brachialis anticus muscle. 



External to the artery is the coraco-brachialis above, and the muscular belly of 

 the bice[)s bflow, V)oth of which slightly overlap the vessel, and at the bend of the 

 ell)o\v the tendon of the biceps. The external vena comes is also to its outer side. 

 The median nerve is in close contact with the outer side of the artery in the upper 

 third of its course, but in the middle tliird crosses the artery obliquely to gain the 

 inner side. 



Internal to the artery in the upper part of its course are the internal cutaneous 

 and the ulnar nerves; the latter nerve, however, leaves the artery about the origin 



Fig. 351. — The Brachial Artery at the Bend of the Elbow, Left Side, Front View, 



POSTERIOR BRANCH 



OF INTERNAL 



CUTANEOUS NERVE 

 ANTERIOR BRANCH 



OF INTERNAL 



CUTANEOUS NERVE 



Biceps muscle 



BRANCH OF MUSCULO- 

 SPIRAL NERVE TO 

 SUPINA TOR L ON(t US 



RADIAL NERVE 



Riulir,] recurrent artery 

 <nnl POSTERIOR ' 

 INTEROSSEOUS 

 NERVE 



Tendon of biceps 



MUSCULO-CUTANEO US 

 NER VE 



Supinator longus muscle 



■f- Radial artery 



of the inferior profunda branch, to make, with that vessel, for the internal con- 

 dyle. Lower down, the internal cutaneous nerve also leaves the artery, by piercing 

 the deep fascia. The median nerve is in close contact with the inner side of the 

 artery in its lower third and at the bend of the elbow. The basilic vein is super- 

 ficial to it, and a little to its inner side in the greater part of its course, but 

 separated from it l)y the deep fascia. The internal vena comes runs along its inner 

 side. 



The Variations in the Brachial Artery 



The chief variations in the brachial artery are: — (1) A high division into its terminal 

 branches. The high division inny occur at any spot in the iionnal course ot" the vessel, but is 

 most common in the upper third of the arm, and least common in the middle third. The two 

 vessels into which the brachial then divides as a rule run parallel tu eacli other to the bend of" the 



