530 
AN ESSAY ON CHRONIC PODOTROCHOLITIS. 
while the original cause of the lameness actually exists in the 
trochlea of the foot. This error arises from the ignorance of prac- 
titioners who have not studied the navicular disease, the obscure 
physiognomy of the affection ; and, above all, the confusion which 
prevails in the symptomatology of “ lame in the shoulder,” which 
has been transformed into a veritable tower of Babel. 
On comparing together the different authors who have given an 
account of the symptoms characterising lamenesses of the shoulder, 
we find a chaos, which, so far from becoming arranged by the pro- 
gress of time, only appears to have become the more confused. 
Some point out as a pathognomonical symptom the abduction of the 
limb in action, the effect of a relaxation of the muscles uniting 
the shoulder to the breast: the action of abduction is also con- 
stantly observable in podotrocholitis. Others, on the contrary, 
pretend that this position is attributable to a contraction of the 
muscles drawing back the scapula. The latter have recourse to 
emollients, the former to excitants, and both relate their instances 
of cure. Again, there are others who regard the contracted action 
of the shoulder as an expression of pain existing in the levator 
humeri muscle; but they are ignorant that this phenomenon like- 
wise appertains to chronic podotrocholitis ; and they do not reflect 
of how little importance the abovementioned muscle is in motion of 
the shoulder. I have cut through it, and the movements of the 
shoulder remained as free as ever*. The flexion of the head and 
chest during progression is also regarded as an invariable symp- 
tom of shoulder-lameness by some practitioners; while others 
consider it to be a positive sign of the existence of an affection of 
the levator humeri muscle. Both parties appear to have lost sight 
of the fact, that the flexor movements of the head and neck are 
observable in other lamenesses besides those of the shoulder, — that 
it is, in fact, inseparable from all such as are at all intense. In 
point of fact, the head and neck are accessory levers, destined by 
nature to assist in the progression of the body ; they ought, con- 
* I have also cut the biceps of the arm, and after the operation I remarked 
a sensible difference in the position and motion of the limb. The angle 
formed by the shoulder with the arm is much less open than that of the op- 
posite extremity ; while, on the other hand, the angle of the arm and the fore- 
arm was much more developed. In walking, the limb operated upon was 
very quickly raised after having been rested on : the animal stumbled fre- 
quently. In retrograde movements this? limb was quite as easily displaced as 
the opposite one, but it embraced a much greater extent of ground : when 
in repose it constantly assumed a direction from above downwards and from 
before backwards. On the second or third day, when the inflammation had 
fully declared itself, these symptoms became more evident ; the limb was 
dragged in circles. It is certain that this effect is attributable not to the 
inactivity of the biceps, but to the tumefaction of the surrounding parts. 
