HOOF LAMENESS. 127 



with the navicular bone, the inferior extremity of the os 

 corona, ligaments uniting the pedal articulation, the tendon 

 of the extensor pedis and of the perforans ; the former in 

 front of the pedal articulation, the latter supporting it from 

 behind. 



The fibro-cartilages, one on each side of the os pedis, are 

 united posteriorly and below to the plantar cushion, a 

 fibrous elastic wedge-shaped mass, on which the navicular 

 bone rests by means of the perforans tendon. 



The keratogenous apparatus covers the parts just men- 

 tioned like a stocking. This apparatus is a continuation of 

 the outer skin of the phalangeal region. It shows the 

 coronary cushion, a rounded prominence situated at the 

 junction of the hoof and skin, and is covered with little 

 prolongations known as papillae. 



The coronary cushion is the matrix of the wall. The 

 podophyllous tissue, or sensitive laminae, line the anterior 

 face of the os pedis. These are very vascular parallel 

 leaves, separated from each other by deep channels, into 

 which the horny leaves of the inner face of the wall are 

 dovetailed. (Chauveau.) 



The diagnosis of the seat of the pain, viz., lameness in 

 the hoof, requires primarily a knowledge of the physical 

 properties of the hoof and anato mo-physiological peculiari- 

 ties of the keratogenous membrane. 



The diagnosis of the seat of lameness only too often is 

 difficult, since the horny box, enveloping the sensitive soft 

 parts, is opaque and unyielding. A happy circumstance, — 

 at least from a clinical standpoint, — is encountered with, 

 namely, disease of the podophyllous membrane, is always 

 painful, therefore producing lameness. 



The soft parts within the hoof, lying between the 



