METATARSAL BONES. 109 



respectively with the three cuneiform bones. On its outer side, in some 

 instances, is a small smooth surface, by which it is articulated to the cuboid 

 bone. Its superior and inferior surfaces are rough, and on its inner border, 

 directed downwards, is a prominent tubercle to which the tendon of the 

 tibialis posticus muscle is attached. 



THE CUNEIFORM BONES. 



These wedge-shaped bones, three in number, are distinguished numerically 

 according to their order from within outwards. They intervene between the 

 scaphoid bone and the three inner metatarsal bones, and present anteriorly 

 and posteriorly smooth surfaces for articulation with those bones. The first 

 or internal cuneiform bone is the largest ; it is narrow above, and thick 

 and rough towards the sole ; its dorsal surface looks inwards and upwards, 

 and is marked by an oblique descending groove, in which the tendon of the 

 tibialis anticus lies ; its external surface, concave and rough inferiorly, is 

 smooth and articular above. The second and third, or middle and ex- 

 ternal, cuneiform bones each present a quadrangular surface superiorly, and 

 a narrower rough edge below, contributing thus to form the transverse arch 

 of the foot. The proximal ends of the three bones are in the same transversa 

 line ; but as the middle bone is the shortest, the internal and external 

 project forwards, so as to articulate laterally not only with the sides of that 

 bone, but also with the base of the second metatarsal bone, which is inserted 

 between them. The outer side of the third cuneiform articulates by a 

 smooth flat surface with the cuboid, and by a small narrow facet (some- 

 times absent) with the fourth metatarsal bone. 



THE METATARSUS. 



The five metatarsal bones are distinguished by numbers, according to 

 their position from within outwards. 



They resemble the metacarpal bones of the hand in being shafted bones, 

 slightly convex from behind forwards on the dorsal aspect, and having 

 irregularly shaped proximal extremities, three-sided shafts, and rounded 

 heads which articulate with the phalanges. The first metatarsal bone is 

 much thicker and more massive, though shorter, than any of the rest. The 

 others diminish in length from the second to the fifth. 



The proximal extremities resemble those of the metacarpal bones exactly 

 as regards the number of bones with which each articulates. The first 

 articulates with one bone, the internal cuneiform ; the second with four 

 bone?, viz. the three cuneiform and the third metatarsal ; the third with 

 three bones, viz. the external cuneiform and the adjacent metatarsals ; the 

 fourth with four bones, viz. the cuboid, external cuneiform, and the adjacent 

 metatarsals ; the fifth with two bones, viz. the cuboid and the fourth meta- 

 tarsal. The fourth, however, is sometimes connected with only three bones, 

 its facet for articulation with the external cuneiform being absent. The 

 tarsal extremity of the first metatarsal bone presents a slightly concave 

 articular surface, and is broad below and narrow above. That of the fifth 

 presents externally a large rough tuberosity which projects beyond the other 

 bones at the outer side of the foot ; and the line of its articulation with the 

 cuboid bone is so oblique that, if prolonged inwards, it would reach the 

 digital end of the first metatarsal bone. The tarsal ends of the remaining 

 three bones are broad and flat above, rough and narrower below, and by 

 their wedge-like form assist in producing the transverse arch of the foot. 



The shafts present in the greater part of their extent a prominent border 



