REGIONAL ANATOMY 31 



1. The Latekal Cartilages. — Each is a flattened plate 

 of cartilage, possessing two faces and four borders separated 

 by four angles. 



The external face is convex, covered by a plexus of veins, 

 and slightly overhangs the pedal bone. The internal face 

 is concave, and covers in front the pedal articulation and 

 the synovial sac, already mentioned as protruding between 

 the antero- and postero-lateral ligaments of that joint. We 

 have already remarked that this is a point of interest to be 



Fig. 16. — External Face of the Outer Lateral Cartilage. 



1, External face of cartilage — (a) its upper border, {b) its posterior border, 

 (c) its anterior border, (d) its inferior border ; 2, the os pedis ; 3, wing of 

 OS pedis. 



remembered in connection with the operation for quittor. 

 Below and behind, the internal face of the cartilage is 

 united to the plantar cushion. 



The upper border, sometimes convex, sometimes straight, 

 is thin and bevelled, and may easily be felt in the living 

 animal. It is this border that the digital vessels cross to 

 gain the foot, and the border is often broken by a deep 

 notch to accommodate them. The inferior border is 

 attached in front to the basilar and retrossal processes. 



