664 
LAMENESS. 
constitutes its defence against concussion ; and any thing that checks, 
arrests, or interferes with the action of that spring, subjects it to 
injury, to bruise, to breach, even to fracture. Again, in regard to 
the hock, that is the identical joint through whose operation the 
grand work of progression is carried on : no wonder, therefore, 
that it should prove out of order oftener than any other of the hind 
joints, or that we should so often discover ulceration in it. Both in 
the navicular and hock joints, therefore, have we great cause to look 
for that which is likety to injure the synovial membrane, or at all 
events excite inflammation in it. The question is, is the ulceration 
a consequence of inflammation, or does the inflammation follow the 
ulcerative disease 1 
A fact that appears to us to throw much light upon this question 
is that of articular lameness in many instances manifesting itself 
“ all of a sudden.” A horse, never lame perhaps in his life, shall 
leave the stable in his ordinary state of perfect soundness, and 
while out drop suddenly lame, and from that moment become and 
continue a lame horse, without there being to the observation of his 
master any thing whatever to account for his lameness. Can such 
a lameness as this — known from experience commonly to prove 
articular — arise from inflammation 1 Can inflammatory action have 
set in all of a sudden ? What, then, seems the feasible way of 
accounting for his lameness, assuming it to be in the joint, most 
likely either the navicular or hock ? Why, that bruise or breach 
or solution of continuity of the synovial membrane has taken place, 
and that this is followed by ulceration and by inflammation. If 
the horse be examined immediately after lameness has befallen 
him, the suspected joint or foot will feel cool — as free at least from 
any extraordinary heat as the fellow one in the opposite- fore or 
hind leg : four-and-twenty or eight-and-forty hours afterwards, 
however, heat becomes detectible, inflammation has set in, and all 
doubt as to the locality of the seat of lameness dispelled. 
Supposing the lame horse to be laid up on the discovery of 
his lameness, it very often happens that after two or three days 
repose he comes out of his stable going much less lame, all but 
sound perhaps : the inflammation that supervened on the injury 
to the synovial membrane, generally of the sub-acute character, 
has in this instance proved a milid attack, and in reality has 
tended rather to the animal’s benefit than otherwise ; has probably 
nearly or quite healed up the breach made in the membrane, and 
so enabled the horse to go comparatively painlessly. A very little, 
however, must be expected to open the breach again, filled up as it 
is only by lymphy effusion ; and so in practice we find it, for let the 
horse be taken out again only but to exercise, and his lameness 
will surely return. 
