414 



herent horn that bears but little or no wear. The sole being now con- 

 vex the diseased tissues are compelled to bear unusual weight by com- 

 ing in contact with the ground, and hence it is these animals are gen- 

 erally incurable cripples. In the majority of cases where the sole is 

 raised to meet the pedal bone and pumiced sole occurs, it is due not to 

 pressure of the bone from within (for the tissues are capable of adapt- 

 ing themselves to the gradual change), but to impaired vitality of the 

 sensitive tissues from the inflammation and the constant concussion and 

 pressure. applied from without during i^rogression. Added to this is to 

 be considered the paring away of the horn by the smith when apj)lying 

 the shoe, thereby keeping the sole at this point too thin. 



Turning up of the toe. — In many cases of laminitis which have be- 

 come chronic it is found that the toe of the foot turns up, and that the 

 heels are longer than natural, while the whole hoof next to the coro- 

 nary band is circled with ridges like the horn of a ram. Even in other 

 cases where recovery has taken i^lace, and in other diseases than lam- 

 initis, these may be found in the wall of the foot, but in these cases the 

 ridges are equally distant from each other all around the foot, while in 

 turning up of the toe the ridges are wide apart at the heels and close 

 together in front, as seen in the figure (Plate xxxi. Fig. 4). These 

 ridges are produced by periods of interfeience with the growth of horn 

 alternating with periods during which a normal or nearly normal 

 growth takes place. When the toe turns up it does so because the cor- 

 onary band in front produces horn very slowly, while at the heels it 

 grows much faster. 



Animals affected with pumiced foot and turning up of the toe during 

 progression always place the abnormally long heel first upon the ground, 

 not because the heel is too long, nor as in acute or subacute laminitis 

 to relieve the pain, but for the simple reason that the animal carries the 

 leg forward with the column of bones in the normal position, and at- 

 tempting to keep them so the heel first comes in contact with the 

 ground, and he then knuckles over at the fetlock in proportion to the 

 amount of foot deformity present as he brings the toe to the surface. 



The pain and impai rment of function in these cases always result 

 in marked atrophy of the mus cles of the forearm and shoulder, and to 

 some extent of the pectorals, while the position of the fore feet ad- 

 vances the scapula joints so far forward as to cause a somewhat sunken 

 appearance of the chest in front, which the laity recognize as a peculiar 

 form of the disease popularly designated as "chest founder." 



Regarding the presence of inflammation during this process, there is 

 no doubt a chronic form exists a long time after these lesions commence, 

 yet it may in time subside and leave the feet free from fever while the 

 other changes still go on. 



The lesions of turning up of the toe are permanent, and are withal the 

 most interesting pathologically of all the complications of laminitis. 



Treatment. — The treatment of laminitis is probably more varied than 

 in other disease, and yet in spite of it a large number of cases recover 



