AN ESSAY ON CHRONIC PODOTROCHOLITIS. 
415 
movement the hind-quarter muscles receive a sudden and very 
disagreeable shock, and the horse, though naturally a pleasant 
trotter, conveys to his rider that short, insupportable sensation 
called bone-setting . This may easily be conceived ; the articula- 
tions are the natural breakers of the shock ; their limited functions 
consequently, considerably diminish the elasticity of the anterior 
limbs. We find here a manner of progression very different to 
that of foundered horses. In founder, the animal endeavours to 
throw the weight on to the heels in order to save the toe, and 
therefore extends the limb considerably, the fetlock joint as much 
as possible, and rests on the heels ; in podotrocholitis, on the con- 
trary, he avoids all pressure on the heels, advances the limb less, 
flexes it but slightly, and endeavours to throw the centre of gravity 
upon the toe. 
We have been occupied for some time with the morbid pheno- 
mena furnished by the limbs ; let us now pass to the local symp- 
toms. 
At first, the hoof presents no alteration that can be considered 
as the consequence of the podotrocholitis ; it is, nevertheless, not 
unusual to meet with various degrees of contraction, its usual form 
being that of partial contraction of the wall. The increase of tem- 
perature, the evident pain produced by compression of the sole and 
wall, the strong and accelerated pulsations of the lateral arteries, 
signs which lead us to be satisfied as to the presence of an inflam- 
mation of the tissues contained in the horny box, are ever wanting 
at the commencement of podotrocholitis, and the two last-mentioned 
symptoms are not perceptible during the whole course of the 
disease. The more frequent pulsations of the lateral arteries are 
considered by Turner as an important sign. I have never observed 
them ; and on this point I perfectly agree with Hausemann, who 
says, “ In these two affections (the navicular disease and ring- 
bone), which bear great analogy with caries, the number of the 
pulsations of the lateral arteries is not augmented. This negative 
symptom is so invariable, that it may serve as a diagnostic to the 
veterinarian.” There is no doubt in my mind that Turner has 
made a mistake, and confounded some other affections of the foot 
accompanied with pulsation of the arteries, with chronic podotro- 
cholitis ; and this supposition acquires more certainty when he 
adds, that in the navicular disease the lameness may be equally 
great as that following fracture of the pastern, an alleged fact I 
have never observed. 
When the affection has existed for several months, for a year 
or more, sometimes a slight degree of tumefaction appears round 
the coronet, accompanied by a little heat and sensibility, in its 
nature analogous to that swelling which succeeds to a partial con- 
