304 
SPAVIN. 
still the horse was not cured of his lameness, but broke down 
again five months afterwards, notwithstanding he was favoured 
at duty — which was at no times hard — as much as possible : 
the result, in fact, being much the same as we should have looked 
for in a case of patched-up disease of the navicular joint. From 
this, and many other similar cases, I cannot therefore help coming 
to the conclusion that disease of synovial membrane is occasionally 
present at a very early period : whether early enough to precede the 
exostosis is another question. 
Mr. Goodwin, in the course of the discussions to which his 
paper — I have made the foregoing extracts from — gave rise, ex- 
pressed his opinions to be, that “ spavin generally commences 
between the two cuneiform bones,” and that the disease, from its 
commencement, consists in “inflammation and ulceration of the 
synovial membrane exostosis being, he thinks, “ a subsequent 
affair unless it be in the case of “ common spavin,” and that from 
the beginning “ was an exostosis*.” Tt being an acknowledged fact 
that in ordinary cases of spavin, accompanied by lameness, exos- 
tosis is either actually present or speedily makes its appearance 
afterwards, which exostosis is of the high description, and it also 
being ascertained that the callus of the exostosis is of that inflamma- 
tory nature which must cause pain, for my own part, I am disposed 
to think that, in the early stage, inflammation of the periosteum and 
consequent effusion constitutes the sole disease ; but that, no sooner 
are the cushion or two large cuneiform bones cemented together by 
effused callous or osseous matter than from the concussion these 
bones in their fixed state must necessarily experience, bruise 
giving rise to inflammation ensues, and this lays the founda- 
tion for the ulceration and caries which follows. In the case 
wherein no exostosis — no spavin — is detectible, it would seem as 
though synovial disease had been set up in the first instance, and 
without such ascribed concussion : it must be remembered, however, 
that — as I stated before — callous or osseous matter may be de- 
posited upon the surfaces of the cushion bones in situations where, 
from being covered by ligament and tendon, and other soft parts, it 
is not to be discovered either by eye or hand ; as indeed proved to 
be the case in one (if not both) of the hocks of the valuable horse 
belonging to our late Sovereign, whose history is related by Mr. 
Goodwin, as copied by myself at page 302. Could post-mortem 
examples be brought forward of disease of joint without any con- 
comitant callous or osseous incrustation, and consequent fixing 
together of the cushion bones, it would of course go to shew that 
* By common spavin, I take it, Mr. Goodwin means the “ knot” or knob of 
bony deposit before alluded to. 
