136 



THE SKELKWN 



Muscles : — 



The third dorsal interosseous. The fourth dorsal interosseous. 



The second palmar interossemis. 



Blood-supply.— The nutrient artery is furnished hy the second interosseous; it 

 enters on the radial side of the shaft, and is directed towards the proximal end. 



Fkj. 147.— The F^oirth (Left) Metacarpal. 



RADIAL SIDE 



FOR THIRD METACARPAL 



FOR MAGNUM 



ULNAR SIDE 



FOR FIFTH METACARPAL 



The Fifth ^Metacarpal is readily distinguished. The carpal facet is convex 

 for the unciform. The ulnar aspect of the base forms a rounded tubercle for the 

 extensor carpi ulnaris, whilst the radial side has a semilunar facet for the fourth 

 metacarpal bone. The radial border of the dorsal surface of the shaft often has a 

 prominent li]) for the fourth dorsal interosseous muscle. 



Fig. 148. — The Fifth (Left) Metacarpal 



RADIAL SIDE 



FOURTH METACARPAL 



ULNAR SIDE 



Muscles : — 



Flexor carpi ulnaris. Fourth dorsal interosseous. 



Extensor carpi ulnaris. Third palmar interosseous. 



Opi)onens minimi digiti. 



Blood-supply.— The nutrient artery is derived from the third interosseous. It 

 enters the shaft on the radial side, and is directed towards the proximal end. 



