THE INTERNAL CUNEIFORM. 145 



tubercle, which serves as a guide to the astragalo- 

 scaphoid articulation, externally broad and rough, and 

 presents an articular surface for the cuboid ; anteriorly 

 are the three facets for the cuneiform bones ; the pos- 

 terior surface is slightly concave for the head of the 

 astragalus. 



THE CUBOID. 



The cuboid articulates anteriorly with the fourth and 

 fifth metatarsal, posteriorly with the os calcis, internally 

 with the scaphoid and external cuneiform. The superior 

 surface is slightly convex and rough ; the external sur- 

 face is narrow, and notched by the tendon of the long 

 peroneal muscle ; inferiorly it is irregular, and presents at 

 its anterior part a groove, which accommodates the 

 tendon of the peroneus longus muscle in its passage 

 across the sole of the foot; behind the groove is the 

 tuberosity of the cuboid for the attachment of plantar 

 ligaments. The internal surface is rough, but presents 

 two articular facets, the posterior or smaller for the 

 scaphoid, the anterior or larger for the external cunei- 

 form. The anterior surface presents two articular sur- 

 faces, which are practically continuous ; the inner, 

 quadrilateral in form, is for the fourth metatarsal ; the 

 outer is triangular, and is for the articulation of the fifth 

 metatarsal bone. The posterior surface is large, slightly 

 concave, and articulates with the os calcis. 



THE INTERNAL CUNEIFORM. 



The internal cuneiform articulates posteriorly with 

 the inner facet on the scaphoid, anteriorly with the first 

 metatarsal bone, externally with the second metatarsal 

 and the middle cuneiform. Its upper surface is convex 

 and rough ; internally it is rounded and subcutaneous ; 



inferiorly it is irregular, and presents a tuberosity for the 



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