THE METATARSAL BONES. 



209 



The Second (Fig. 147) is the longest and largest of the remaining metatarsal 

 bones, being prolonged backAvard into the recess formed between the three cunei- 

 form bones. Its ten-sal extremity is broad above, narrow and rough below. It 

 presents four articular surfaces : one behind, of a triangular form, for articulation 

 with the middle cuneiform; one at the upper part of its internal lateral surface, 

 for articulation with the internal cuneiform : and two on its external lateral sur- 

 face an upper and a lower, separated by a rough non-articular interval. Each of 

 these articular surfaces is divided by a vertical ridge into two facets, thus making 

 four facets ; the two anterior of these articulate with the third metatarsal ; the 

 two posterior (sometimes continuous) with the external cuneiform. In addition 



For third / 



metatarsal. / 



Occasional 

 facet for first 

 metatarsal. 

 For middle cuneiform. 



FIG. 147. The second metatarsal. (Left.) 



For external 

 cuneiform. 



For second metatarsal. For fourth 



For middle cuneiform. metatarsal. 



FIG. 148. The third metatarsal. (Left.) 



to these articular surfaces there is occasionally a fifth when this bone articulates 

 with the first metatarsal bone. It is oval in shape, and is situated on the inner 

 side of the shaft near the base. 



The facets on the tarsal extremity of the second metatarsal bone serve at 

 once to distinguish it from the rest, and to indicate the foot to which it belongs ; 

 there being one facet at the upper angle of the internal surface, and two facets, 

 each subdivided into two parts, on the external surface, pointing to the side to 

 which the bone belongs. The fact that the two posterior subdivisions of these 

 external facets sometimes run into one should not be forgotten. 



Attachment of Muscles. To four : the Adductor obliquus hallucis, First and 

 Second dorsal interosseous, and a slip from the tendon of the Tibialis posticus; 

 occasionally also a slip from the Peroneus longus. 



, The Third (Fig. 148) articulates behind, by means of a triangular smooth 

 surface, with the external cuneiform ; on its inner side, by two facets, with the 

 second metatarsal; and on its outer side, by a single facet, with the fourth meta- 

 tarsal. The latter facet is of circular form and situated at the upper angle of 

 the base. 



The third metatarsal is knoAvn by its having at its tarsal end two undivided 

 facets on the inner side, and a single facet on the outer. This distinguishes it 

 from the second metatarsal, in which the two facets, found on one side of its 

 tarsal end, are each subdivided into two. The single facet (when the bone is put 

 in its natural position) is on the side to which the bone belongs. 



14 



