198 



THE SKELETON 



attachment of ligaments. On the lateral surface near its posterior border is a vertical facet, 

 sometimes bilobed, for the third cuneiform, and occasionally a second facet at the anterior 

 inferior angle. The superior surface forms the square-cut base of the wedge and is rough for 

 the attachment of ligaments. The inferior surface is sharp and rough for ligaments and a slip 

 of the tendon of the tibialis posterior. 



Fig. 238. — The Left Second Cuneiform. (Medial surface.) 



For first cuneiform 

 For second metatarsal 



Articulations. — With the navicular behind, second metatarsal in front, third cuneiform on 

 the lateral side, and first cuneiform on the medial side. 



Ossification. — From a single nucleus which appears in the fourth year. 



The third cuneiform bone (figs. 240, 241) also placed with the broad end directed upward 

 and the narrow end downward, is distinguished by the oblong shape of its base. Like the 



Fig. 239. — The Left Second Cuneiform. (Lateral surface.) 



-For third cuneiform 



For navicular 



Occasional facet for third cuneiform 



second cuneiform, the posterior surface presents a triangular facet for the navicular; and the 

 anterior surface a triangular facet, longer and narrower, for the third inetatarsal. The medial 

 surface lias a large facet extending along the posterior border for the second cuneiform, and 

 along the anterior border a narrow irregular facet for the lateral side of the base of the second 

 metatarsal. Occasionally, a small facet is present near the anterior inferior angle for the second 



Fig. 240. — The Left Third Cuneiform. (Medial surface.) 



4 



For second cuneiform 



For naviculeir 



Foi second metatarsal. The circular 

 facet near the inferior angle is for 

 the second cuneiform 



cuneiform. The lateral surface has a large distinctive facet near its posterior suj^erior angle 

 for the cuboid, and at the anterior superior angle there is usually a small facet for the medial 

 side of the base of the fourth metatarsal. The superior surface, ol)long in shai)e, is rough for 

 ligaments, and the inferior, forming a rounded margin, receives a slip of the tibialis posterior 

 and gives origin to a few fil)res of tlie flexor hallucis brevis. 



Vic. 211. — 1"iiK Lf-ft 'I'muD Cuneiform. (Lateral surface.) 



For fourth metatarsal 

 For third metatarsal 



For cuboid 



I 



Articulations. — With the navicular behind, third metartarsal in front, cuboid and fourth 

 metatarsal on the lateral side, second cuneiform and second metatarsal on the medial side. 

 Ossification. -A single nucleus appears in the course of the first year. 



