THE CUNEIFORM BOXES. 305 



Articulations. With four bones : astragalus and three cuneiform ; occasionally 

 als<> with the cuboid. 



Attachment of Muscles. Pan of the Tibialis posticus. 



The Cuneiform Bones. 



The Cuneiform Bones have received their name from their wedge-like shape 



;i wedge : ////"/. likeness). They form, with the cuboid, the anterior 



m w of the tarsus, being placed between the navicular behind, the three innermost 



metatarsal bones in front, and the cuboid externally. They are called the first^ 



'. and third, counting from the inner to the outer side of the foot, and, 



from their position. internal, inlddb:. and external. 



The Internal Cuneiform is the largest of the three. It is situated at the inner 

 side of the foot, between the navicular behind and the base of the first metatarsal 

 in front. It may be distinguished, from the other two by its large size, and its 

 more irregular, wedge-like form. Without the others, it may be known by the 

 large kidney-shaped anterior articulating surface and by the prominence on the 

 inferior or plantar surface for the attachment of the Tibialis posticus. It presents 

 fr examination six surfaces. 



The internal surface is subcutaneous, and forms part of the inner border of the 



: it is broad, quadrilateral, and presents at its anterior inferior angle a smooth 

 oval facet, into which the tendon of the Tibialis anticus is partially inserted ; in 

 the rest of its extent it is rough, for the attachment of ligaments. The external 

 ' is concave, presenting, along its superior and posterior borders, a narrow 

 reversed L-shaped surface for articulation with the middle cuneiform behind, and 

 second metatarsal bone in front; in the rest of its extent it is rough for the 

 attachment of ligaments and part of the tendon of the Peroneus longus. The 

 /,-,/ xurf'.t'--' :. kidney-shaped, much larger than the posterior, articulates with 

 the metatarsal bone of the great toe. Tbepotterior surface is triangular, concave* 

 and articulates with the innermost and largest of the three facets on the anterior 

 surface of the navicular. The inferior or plantar surface is rough, and presents a 

 prominent tuberosity at its back part for the attachment of part of the tendon of 

 the Tibialis posticus. It also gives attachment in front to part of the tendon of the 

 the Tibialis anticus. The sup^ri"i- surface is the narrow-pointed end of the wedge, 

 which is directed upward and outward ; it is rough for the attachment of ligaments. 



To ascertain to which side the bone belongs, hold it so that its superior narrow 

 edge looks upward, and the long, kidney-shaped, articular surface forward ; the 

 external surface, marked by its vertical and horizontal articular facets, will point 

 to the side to which it belongs. 



Articulations. With four bones : navicular, middle cuneiform, first and second 

 metatarsal bones. 



Attachment of Muscles. To three : the Tibialis anticus and posticus. and 

 Peroneus longus. 



The Middle Cuneiform, the smallest of the three, is of very regular wedge-like 

 form, the broad extremity being placed upward, the narrow end downward. It 

 is situated between the other two bones of the same name, and articulates with 

 the navicular behind and the second metatarsal in front. It may be distinguished 

 from the external cuneiform bone, which it much resembles in general appearance, 

 by the articular facet, of angular form, which runs round the upper and back part 

 of its inner surface : and if the two bones from the same foot are together, the 

 middle cuneiform is much the smaller. 



The anteri'n' .>-///;f'./o ;. triangular in form and narrower than the posterior, 

 articulates with the base of the second metatarsal bone. The posterior surface, 

 als<> triangular, articulates with the navicular. The internal surface presents a 

 reversed L-shaped articular facet, running along the superior and posterior borders, 

 for articulation with the internal cuneiform, and is rough in the rest of its extent 

 for the attachment of ligaments. The external surface presents posteriorly a 

 smooth facet for articulation with the external cuneiform bone. The sup- 



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