THE BONES OF THE LOWER LIMB 



263 



Structure of the Cuneiform Bones. — ^The structure of each is that 

 of a short bone. 



\\'hen the cuneiform bones are in position their posterior surfaces 

 are on the same transverse plane, but the anterior surfaces of the 



Dorsal Aspect 



For 4th Metatarsal 

 (inconstant) 



Anterior Surface of External' 

 Cuneiform for 3rd Metatarsal ' 



For 2nd Metatarsal' 



I Anterior Surface of Internal 

 i Cuneiform for ist Metatarsal 



'For 2nd Metatarsal 



Anterior Surface of Middle Cuneiform 

 for 2nd Metatarsal 



Fig. 155. — The Right Cuneiform Bones (Axtero-scperior View). 



internal and external project farther forwards than that of the 

 middle. In this manner a recess is formed, into which the base 

 of the second tnetatarsal bone is received. 



The Cuboid Bone. 



The cuboid bone is characterized by its irregularly cubical shape, 

 and by the groove and ridge on its plantar aspect. It is situated on 

 the outer border of the foot, where it lies between the os calcis 

 and the fourth and fifth metatarsal bones. The anterior surface 

 has its cartilage divided by a vertical ridge into two facets — an 

 inner quadrilateral for the fourth metatarsal, and an outer triangular 

 for the fifth metatarsal. The posterior surface presents a large, 

 somewhat triangular, facet, narrow towards the sole and deep in- 

 ternally, which is convex from above downwards and outwards, 

 and concave from side to side. It articulates with the os calcis, 

 and its internal and inferior angle, called the calcaneal process, 

 projects backwards for a little beneath that bone. Below and 

 inside the calcaneal process there may be a facet for the head of 

 the astragalus. The internal surface, which is extensive and 

 vertically disposed, presents a large, almost circular, facet for the 

 external cuneiform, near the centre and extending to the dorsal 

 surface. Behind this, and usually continuous with it, there may be 

 a small facet for the navicular, the remainder of the surface being 

 rough and ligamentous. The external surface, which is really a 



