THE LATERAL CARTILAGES. 



47 



lateral cartilage ; a, insertions of the various ligaments 

 attaclied to lateral cartilage ; b, furrow leading to plantar 

 foramen ; c, point of insertion of ligament connecting the 

 coronet bone and lateral cartilage ; d, point of insertion 

 of lateral ligament of navicular bone (postero-lateral 

 ligament). 



tween these are channels for a rich venous network. About 

 the centre of the inner surface, or rather nearer its anterior 

 margin, can usually be found a well-marked furrow (l) running 

 from above down- 

 wards and forwards 

 towards the plantar 

 groove. In this lies -^ 

 the large vessel which 

 supplies the pedal 

 bone. Close to the 

 lower and anterior 

 angle are attached 

 the postero - lateral 

 licfaments of the 



o 



pnffnn ^n^^^i ( rl^ Frnm FiG. 30.— Postero-lateral view of pedal bone and inner 

 LOmnjumn^(t;. Jium lateral cartilage. ^, pedal bone ;£, inner surface of 



here runs a strong, 

 fibrous cord, the liga- 

 ment connecting the 

 lateral cartilage and 

 bulbs of the frog to the lateral surface of the pastern bone (figs. 

 31, c, and 33, cl). The upper border is thin, and usually inclined 

 inwards, but this does not obtain in every foot ; in some it 

 is upright, in others more or less turned outwards. The lower 

 border is the thickest portion of the cartilage. In front it is 

 united with the wing of the os pedis, in part directly, in part 

 by the ligaments attached in common to it and to the pedal 

 or navicular bones (fig. 29, c). The notch in the wing of the 

 pedal bone is closed by a mass of cartilage, save for a small 

 foramen, which permits of vessels passing to the sensitive struc- 

 tures. The site of this foramen is where ossification of the 

 lateral cartilage usually begins. The posterior part of the lower 

 border inclines inwards (fig. 28), but from this point, in an up- 

 ward direction, the usual trend is outwards. The tissue is here 

 in such close union with the plantar cushion, partly through 

 cartilaginous, partly through fibrous connections, that the two 

 form a common mass, in which no distinct boundary can be 

 detected (fig. 35). The anterior border runs obliquely from 

 above downwards and backwards, and is closely connected with 

 the lateral ligaments of the pedal joint (fig. 29, a), with which 

 it to some extent unites. The posterior border runs in the 



