644 OPEEATIOXS ON THE FOOT. 



stable flooi-. The horse which has both feet diseased in constantly 

 in motion, to such an extent that his shoes are entirely worn in a 

 few days. 



At times the pain is so great that it gives rise to general symp- 

 toms ; the animal becomes anxious, loses his appetite, refuses his 

 food, lies down most of the time, and rises only with difficulty. 



II. Cotnplications. — We have already seen that quarter cracks 

 and dry cordis are common affections of contracted feet. Exos- 

 tosis of the phalangeal region is also commonly met in such feet, 

 especially side-bones. Knuckling, and diseases of the tendons 

 and of their sheaths are also often caused by contractions of the 

 feet. The rest of the foot on its whole surface is thus perverted 

 and the tendons become retracted, painful and swollen. 



Navicular disease is so often met with in company with con- 

 tracted feet, that one disease is frequently mistaken for the other. 

 Laminitis has been said to be also one of the complications ; if 

 so, it is at least quite rare in its occurrence. 



Tetanus has sometimes been observed among its associations, 

 and Hartmann attributes the development of so-called idioj^athic 

 cases of that disease to this condition of the feet. 



The emaciation of the affected leg is a complication seen also, 

 with other forms of lameness. 



III. Pathological Anatomy. — We have indicated the external 

 changes of the hoof. The tissues that have been long enclosed in 

 the contracted foot become atrophied ; molecular changes do not 

 take place as in the normal state ; they become changed in asjoect, 

 composition and properties ; they become denser and more com- 

 pact, and are no more able to fulfill, to the same extent, then," 

 physiological functions. 



The plantar cushion is so completely pressed upon itself that 

 the stratified structure of its fibrous layers can scarcely be dis- 

 tinguished, and the presence in the interstices of the yellow fibrous 

 substance is with difficulty observed. It forms only a homogene- 

 ous mass, whitish in color, resisting in consistency, and lardac- 

 eous in aspect The dilated bulbs which are above the cushion 

 are also considerably diminished in size, and present, when cut 

 through, a uniform white color, its composing substance being 

 reduced to a single inelastic mass. 



The ungueal phalanx becomes deformed by degrees, loses its 

 circular shape and becomes of an elongated oval form. Its lateral 



