678 



OPERATIONS ON THE FOOT. 



the horny box. The external surface of the wall, instead of be- 

 ing smooth, as in physiological conditions, presents, on the con- 

 trary', a roughened aj^jjearance, which results from the presence 

 of circles of ridges and circular grooves, placed one above the 

 other and extending from one heel to the other. A remarkable 

 peculiarity is here observed in the fact that in the anterior part of 

 the nail the circles are quite near each other, while, on the con- 

 irary, upon the lateral parts they are separated by much wider 

 grooves. "When, then, at the toe, the wall has some difficulty in 

 growing downward, on account, probably, of the internal adhes- 

 ions between the podophyllous and keraphyllous tissues; the 

 heels, on the contrary, grow without difficulty, and thus obtain a 

 relative height superior, and sometimes even equal, to that of the 

 toe. Often at the mammae and quarters of the foot contractions 

 are seen, and longitudinal grooves running from the coronary 

 band to the plantar surface, reminding one of the lesions usually 



met Avith in encastelure. 



Considered on the side of 

 the inferior face, the old f ound- 

 dered hoof offers four remark- 

 able lesions (Fig. 516). Besides 

 its oval form, a disposition al- 

 together different from that of 

 the normal state, the sole is 

 convex in all the anterior part 

 of the plantar region, especially at the point of the frog. There 

 exists at that point a transversal tumor or enlargement, projecting 

 sufficiently to exceed in height the inferior border of the wall. The 

 solar sheet has been pushed outward by the pressure against the 

 superior face from the contents of the horny box, and the foot is 

 convex. This convexity never equals the entire extent of the foot, 

 the deformity ending at the boundary of the inferior border of 

 the bars, beyond which and backward are found the cavities of the 



Fig. 516.— Chronic Laminitls, last stage. 



also higher (Fig. 517). The center of this tumor or enlargement 

 of the sole is often flexible under the pressure of the finger, and 

 generally bleeds easily on the application of the sharp tools of the 

 blacksmith. It is not rare to see the sole perforated through and 

 through and showing the inferior border of the os pedis project- 

 ing through the border of the bone, which then soon becomes 



