174 



PRACTICAL ANATOMY. 



the presence of the ulnar nerve on its inner or ulnar side. Find also where this 

 nerve gives off its dorsal ulnar cutaneous branch, to be distributed to the dorsum 

 of the little finger and half of the ring finger. 



The Cubital Fossa. Figure 1 18 shows the superficial dissection of this area 

 you have already made. Now cut the bicipital fascia with scissors, and develop 

 the brachial artery and its branches, and make your dissection look like figure 

 1 19. Note (i) the brachial artery ; (2) to the inner side of this artery the median 

 nerve; (3) to the outer side of the artery the tendon of the biceps muscle; 

 (4) to the outer side of the tendon of the biceps, see the musculo-spiral nerve, 

 deeply located between the brachialis anticus muscle and the supinator longus 

 muscle, dividing into the radial and posterior interosseous nerves. Find also 



POSTERIOR BRANCH 



OF INTERNAL 



CUTANEO US NER VE 

 ANTERIOR BRANCH 



OF INTERNAL 



CUTANEOUS NERVE 



Brachial artery 



BRANCH TO 

 PRONATOR TERES 



Bicipital fascia, cut 



Pronator radii tercs 

 muscle 



MEDIAN NERVE 



Ulnar artery 



Biceps muscle 



BRANCH OF MUSCULO- 

 SPIRA L NER VE TO 

 SUPINA TOR LONG US 



RADIAL NERVE 



Radial recurrent artery 

 ,i>,,l POSTERIOR 

 INTEROSSEO US 

 NERVK 



Tendon of biceps 



MUSCUL O- CUTA NEO US 

 NERVE 



' Supinator longus muscle 



j Radial artery 



FIG. 119. THE BKACHIAI. ARTERY AT TIN I'.KND OK THE Ku;\v. 



the muscular branches to the pronator radii tores and supinator longus muscles, 

 from the median and musculo-spiral nerves respectively. 



Carefully remove the deep fascia from the muscles and your dissection of the 

 cubital fossa will look like figure I 20. You will now find each tendon individual;}-, 

 as in figure 120, near the annular ligament; trace it up to the muscular mass 

 from which it comes ; then refer to the figure for the name of the structure. 

 Caution : As you thus in cleaning the muscles one by one remove the deep fasc ia 

 from the muscles, do not destroy the superficial vessels and nerves divide only 

 the connective tissue-. 



For convenience of dissection develop the muscles of first group (Fig. 120): 

 I. Pronator radii tcrcs : origin, inner comlyle and coronoid process. 



