ANATOMY AND PHYSIOLOGY OF THE FOOT 



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ANATOMY AND PHYSIOLOGY OF THE FOOT 



Some knowledge of the structure of the foot and of its functions is 

 necessary to an understanding of the principles of horse-shoeing. The 

 hoof is only a layer of horn covering very sensitive parts and affording a 

 base of support for the limb. A damaged hoof cannot properly protect the 

 parts within, and a deformed hoof places the whole limb at a disadvantage 

 even as a column of support — much more 

 so as a propelling organ, when great effort 

 is required for draught, or quick move- 

 ments for pace. 



The hoof is not a regular geometrical 

 figure, it is an irregular one (fig. 624), 

 and this irregular form must Ije followed 

 in shoeing. If the two front feet be looked 

 at on the ground it will be seen that they 

 are similar in form and size, that the inner 

 surface is more upright than the outer, 

 and that the hoof is much higher in front 

 than behind. 



The Wall (fig. 625) is the part of 

 the horn formina; the front and sides of 

 the hoof It g-rows downwards from the 

 coronet, and as it slopes forward and is 

 constantly growing, there is a continuous 

 lengthening of the toe. The eff"ect of ex- 

 cessive growth is therefore to bring the 

 bearing surface of the foot out of proper 

 relation to the lea;, and all overgrown feet aff'ord a disadvantageous 

 position for the horse standing or moving. When a horse is shod his 

 hoof continues growing, and if the shoe be retained too long, the hoof 

 gets disproportionate, and may cause either stuml)liug or injury to the 

 tendons. The angle at which the front of the wall slopes is a useful 

 guide to the proportions of the hoof It .should be about 45 degrees. 

 When the toe is too long the wall slopes too much, wlien the heels are too 

 high the front of the wall is too upright (fig. 631). The wall is thicker 

 at the toe than at the heels, and as this variation is gradual from front 

 to back, so nails may l)e driven into it with less danger towards the 

 toe. The wall does not vary in thickness vertically, so a good workman 

 may safely drive a nail to any reasonable height in its substance. The 



Fig. 624.— Normal Foot: front view, 

 showing slopes of (a) outer wall and 

 (b) inner wall 



