Till-: UK. \('1I1AL 1'LKXCS 



923 



muscles at the hack of the forearm. \\ here it come,- into relat ion \vit h t he posterior 

 iiiten>s-enti> artery, anil accompanies it across the abductor polhcis longus. At the 

 lower bonier of tlie latter muscle it gives off a branch to t he extensor pollicis lon^us. 

 and allot her which crosses this muscle to the extensor indicis proprius. Continuing 

 distalwards as the dorsal ant ilirachial interosseous nerve it leaves the posterior inter- 

 osseous artery, dips beneath the extensor [xillicis lonirus. and comes into relat ion with 

 the anterior interosseous artery. It accompanies t his artery upon the interosseous 

 membrane and the back of the radius, passes through t he groove for the extensor digi- 

 toriini commiinis and extensor indicis propriu.s to the back of the wrist, and terminate- 



FlO. 681. A. DisSKi-riiiN- (IF THE OCTANKOCS XKKVF.S o\ THE DORSAL ASPECT OF THE 



HAND AND I''IN<;I:US. (II. St. J. B.) 

 The brandies of the median nerve are shown in black 



/"</.'vi/, /;/;.( yen 

 oh' i'i..\.ii: .V/.7.T/. 



BRAKCII < IF 



ur: in All 



M:I:\'E 



iu:.\y<-ll HI-' HAIIIM. (MUSCVLO-SfXSAL) 



si 1-1:1:1 II-IM. I:M>L\L (t:\tn.\L) .\i;i:i'i-: 



in a gangliform enlargement which gives branches to the carpal articulations. The 

 muscles supplied by the deep radial (posterior interosseous) nerve are the extensor 

 carpi radialis brevis. brachio-radialis (supinator lonfrus). extensor diiiitorum com- 

 numis, extensor dijriti (|iiinti projirius. extensor carpi ulnaris. extensor indicis ]>ro- 

 prius. and the extensor muscles of the thumb. The supinator (brevis) receives two 

 twigs, one of which is given off before the nerve pierces the muscle and the other 

 while it is passing through it. 



The superficial radial (radial) nerve is somewhat smaller than the derp radial 

 (posterior interosseous), and is a purely cutaneous nerve. It runs downwards under 

 cover of the brachio-radialis. passing in front of the elbow-joint, the radial recurrent 



