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Anatomy of Skeleton 



Inner Cuneiform. A triangular facet behind, with base below, for scaphoid, and 

 a larger kidney-shaped surface in front for the first metatarsal. Inner surface convex 

 from above downwards, conforming with the rounded inner border of the foot, marked 

 by ligaments, covered by skin and superficial tissues, and crossed by tendon of Tibialis 

 anticus, which is partly inserted into it : an oval facet below and in front is partly 

 for its insertion and partly for a bursa under a sesamoid cartilage in the fibres that pass 

 over it to reach the first metatarsal. 



The outer surface is on the whole concave. It has an elongated facet along its 

 back and upper margins for the second cuneiform and a small surface for the second 

 metatarsal in its upper and front corner, continuous with the last ; otherwise this 

 aspect is rough for ligamentous fibres (interosseous) of the transverse set joining it to the 

 second cuneiform and metatarsal, but an impression in its lower and front part fre- 

 quently shows insertion of Peroneus longus. The upper and front ligamentous fibres 

 constitute " Lisfranc's ligament." 



The thick base is covered by ligamentous fibres and expansions from the tendon 

 of Tibialis posticus : superficial to these lie the fleshy mass of the short flexor and tendon 



for mela.nn.JI- 



facet for middle 

 cuneiform 



inierfiiarj 



AffKtut 

 FIG. 151. Internal cuneiform, left side. Inner and outer views. 



of long flexor of the big toe and the more superficial structures, and the bone rests 

 through these on the ground when sufficient weight is thrown on the foot to depress 

 the inner arch to a slight extent. 



Middle Cuneiform. Triangular facet in front for second metatarsal and behind 

 for scaphoid. Dorsally it has slight ligamentous markings. Internally a long V- 

 shaped facet along the back and upper margins for the inner cuneiform : the rest 

 of the surface for attachment of intercuneiform ligaments of the transverse set. Exter- 

 nally a long facet, slightly narrowed in the middle, along its posterior margin, for the 

 outer cuneiform : the remaining surface ligamentous. 



Outer Cuneiform. -Dorsal surface has slight ligamentous markings. Posterior 

 facet for scaphoid does not take up the whole of this aspect, as a blunt point of bone 

 projects slightly below it. Internally a long facet behind for middle cuneiform, and 

 another, usually divided, along the front border for second metatarsal : the remaining 

 surface ligamentous. Externally a rounded facet for cuboid behind and above, a 

 small one for fourth metatarsal * in front and above, and the rest of the surface rough 

 for ligaments of the transverse groups. It carries the third metatarsal alone on its 

 front aspect. 



The cuneiforms show a slight general convexity from side to side on their dorsal 



* The connection is frequently ligamentous, when no facet is present. 



