SHOULDER, ARM, FOREARM, HAND. POSTERIOR PART. 347 



(3) Then lift the nerve on your finger and follow the same by dividing the'con- 

 nective tissue in the direction of the branches given off. 



Remember that the circumflex nerve sends its cutaneous branches to the skin 

 over the insertion of the deltoid, according to Hilton's law. (Fig. 241.) The 

 musculo-cutaneous nerve sends a cutaneous branch to supply the skin over the 

 insertion of the supinator longus, according to the same law, since this muscle 

 is one of the forearm flexors and is supplied by the musculo-cutaneous. The 



DORSAL BRANCH 

 OF ULNAR 



BRANCH OF 

 MEDIAN 

 NERVE 



BRANCH OF MUSCULO-SPIRAL 



RADIAL NERYE 



FIG. 242. A DISSECTION OF THE CUTANEOUS NERVES ON THE DORSAL ASPECT OF THE 



HAND AND FINGKRS. (H. St. J. B.) 

 The branches of the median nerve are shown in black. 



distribution of the radial nerve is explained in the same way. You will note that 

 the cutaneous nerves divide into numerous small branches. (Fig. 242.) 



The deep fascia is quite heavy below the elbow, but thin above the elbow. 

 Opposite the wrist it takes the name posterior annular ligament. Notice in figure 

 243 that the muscles all become tendinous before they reach this ligament. 

 Remove the deep fascia as in the figure. "Dorsal fascia" is the name for the 

 deep fascia on the back of the hand. 



