226 



OSTEOLOGY 



For navicular 



Volar 



surface 



For greater 

 multangular 



smooth, and slightly concave, articulates with the navicular. The inferior surface 

 articulates with the proximal end of the second metacarpal bone; it is convex from 

 side to side, concave from before backward and subdivided by an elevated ridge into 



two unequal facets. The dorsal and volar 

 surfaces are rough for the attachment of 

 ligaments, the former being the larger 

 of the two. The lateral surface, convex 

 and smooth, articulates with the greater 

 multangular. The medial surface is con- 

 cave and smooth in front, for artic- 

 ulation with the capitate; rough behind, 

 for the attachment of an interosseous 

 ligament. 



For 



capitate 



Dorsal 

 surface 



FIG. 226. The left lesser multangular bone 



For 2n<T 



metacarpal 



Articulations. The lesser multangular articulates with four bones: the navicular proximally, 

 second metacarpal distally, greater multangular laterally, and capitate medially. 



The Capitate Bone (os capitatum; os magnum') (Fig. 227). The capitate bone 

 is the largest of the carpal bones, and occupies the center of the wrist. It presents, 

 above, a rounded portion or head, which is received into the concavity formed by 



For lunate 



For 



navicular 



For lesser 

 multangular 



For 



hamate 



For 3rd 



For 2nd metacarpal 

 metacarpal 



For 4lh metacarpal Volar surface 



Fia. 227. The left capitate bone. 



the navicular and lunate; a constricted portion or neck; and below this, the body. 

 The superior surface is round, smooth, and articulates with the lunate. The inferior 

 surface is divided by two ridges into three facets, for articulation with the second, 

 third, and fourth metacarpal bones, that for the third being the largest. The 

 dorsal surface is broad and rough. The volar surface is narrow, rounded, and rough, 

 for the attachment of ligaments and a part of the Adductor pollicis obliquus. 



For lunate 



For triangular 



For capitate 

 For 4th metacarpal 



For 5th metacarpal Hamulus 



For 5th metacarpal 



FIG. 228. The left hamate bone. 



The lateral surface articulates with the lesser multangular by a small facet at 

 its anterior inferior angle, behind which is a rough depression for the attach- 

 ment of an interosseous ligament. Above this is a deep, rough groove, forming 

 part of the neck, and serving for the attachment of ligaments; it is bounded supe- 

 riorly by a smooth, convex surface, for articulation with the navicular. The medial 



