OSTEOPOROSIS. 
551 
heel. As this animal was being conditioned for fast work, 1 
thought it not at all strange under the existing circumstances 
that he should bruise the heel, which seemed a valid cause for 
his lameness. I diagnosed the trouble navicular arthritis. 
On the ioth of March I was called again ; the lameness 
had then left the fore extremity, and at that time was very pro¬ 
nounced in the left hip. It was at this time that I began to 
mistrust the impending trouble, whereupon a thorough ex¬ 
amination was made which proved beyond doubt my suspi¬ 
cion. This case was watched daily from this time until May 
25th, when it was deemed as only human to end the suffer¬ 
ings of the animal. During this period the disease presented 
the following symptoms : A constant degree of lameness in 
some one or more of the extremities at the same time, the 
peculiarity of which was, when lame in two limbs at the same 
time, it would be that of the hind and fore limbs of the oppo¬ 
site side. The greatest degree of lameness existing was in the 
left hind leg, which became straight as the disease progressed, 
to such extent that a straight line drawn from the irochanter- 
major extremities to the os pedis would touch the entire length 
of all the long bones of the leg. A general atrophy of the 
muscles of the limbs, and at times an inability to rise without 
assistance; appetite, but toward the last there was a disincli¬ 
nation to masticate ordinary food, gruels being administered 
instead. The bowels remained normal throughout, urine 
natural in quantity and color. 
Post mortem examination presented a most interesting 
revelation. I will relate a few of the most prominent lesions. 
The animal was bled for the purpose of dissection. The muscles 
of the legs were paler than natural, and maculate. In disarticu¬ 
lating the limbs from the trunk, and especially the bones of each 
limb one from the other, the interior of the joints presented a 
contrast. The articular cartilage was of a purplish hue, much 
thinner than natural and in some instances entirely lost, leav¬ 
ing the margin of the articulation at that point quite exposed. 
In others the articular cartilage was of natural thickness, but 
easily detached from the bone. In these the synovial fluid 
was darker in color and in some instances streaked with 
