ANTERI(31l ANTIBRACHIAL GllOUP. 



223 



EXTENSOR METACARPI OBLIQUUS. 



{Radio-premetacarpp.us.) 



(Fig. 78. A.) 



This muscle is situated on the in- 

 fero-anterior part of the radius, and is 

 triangular and penniform ; aponeurotic 

 above, it terminates in a small tendon, 

 which crosses obliquely the inferior 

 extremity of the anterior surface of 

 the radius, under the extensor pedis, 

 and over the extensor metacarpi 

 magnus tendon. 



Origin. — From the external border 

 of the radius. Its tendon passes 

 through the oblique groove on the 

 antero-internal part of the distal end 

 of the radius, where there is a synovial 

 sheath. 



Insertion. — The head of the inner 

 metacarpal bone. 



Relation. — Anteriorly with the ex- 

 tensor pedis and the fascia ; posteriorly 

 with the extensor metacarpi magnus 

 and the bone. 



Action. — To extend the metacarpus 

 and rotate it slightly, carrying the 

 inner aspect forwards. 



EXTENSOR PEDIS. 



( Epitrocldeo-prephalangeus. ) 



(Fig. 78. i; Fig. SO./.) 



Placed on the antero-external part 

 of the fore-arm, it is long and pyra- 

 midal, extending downwards ; fleshy 

 above, its belly is bifid inferiorly, and 

 terminates in a long tendon, which is 

 double, and commences about the 

 inferior third of the radius. 



Fig. 80. 



External view of the muscles of the 

 anterior limb— showing the deeper 

 ones of the upper region, a a, Postea- 

 spinatus minor ; h, Deep portion of 

 postea-spiuatus ; c. Flexor brachii 

 divided, and the upper part raised; 

 c', Its tendon, which fits the bicipital 

 groove ; d, Humeralis obliquus ; e. An- 

 coneus ; /, Extensor pedis ; <j, Thier- 

 nesse's muscle ; 7i, Phillips' muscle ; 

 W , Its tendon. 



