PATHOLOGY OF SPAVIN. 79 



present at a very early period : whether early enough to j^recede 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 

 beins: 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 



