72 PATHOLOGY OF SPAVIN. 



much weight thrown upon these bones and joints, shocks of 

 concussion coming upon them, excite inflammatory action in 

 their articular cavities, and outward connexions and coverings, 

 and the result is, ulceration of the one, ossification and exos- 

 tosis of the other. So long as lameness is present without tumour 

 or other external sign, it would seem either that the disease 

 was confined to the articulating surfaces, or else that osseous 

 deposition took place in parts where, externally, it could not be 

 detected. It must be remembered, however, that the ordinary 

 case of spavin consists in the appearance of exostosis and lameness 

 together : at least, from any report or history we in general obtain, 

 we are unable to say which of the two has made its appearance 

 the first. Therefore would it seem, in the generality of cases of 

 spavin, exostosis being a primary symptom, that the inflammation 

 originated in the ligamentary and periosteal tissues uniting and 

 clothing the cuneiform bones ; and that the inner in preference to 

 the outer side of the hock joint became affected from the stretch 

 and strain on that part being the greatest, in consequence of the 

 inclination of the limb and preponderance of the Aveight to the 

 inner side, rather than, perhaps, to the circumstance of the inde- 

 pendent articulation of the inner small metatarsal bone, since we 

 know that exostosis is not confined to the spavin-place. In post- 

 mortem examinations we find coatings of osseous matter extending 

 round upon \\iQ front of the cuneiform joints : and such more fre- 

 quently, I believe, exist in this situation than we are apt to imagine; 

 it being in the living subject difhcult, often impossible, to detect 

 exostosis hereabouts, on account of the osseous deposit being 

 concealed by the ligaments of the cuneiform bones, as well as by 

 the tendon of the flexor metatarsi. Cases, however, do present 

 themselves, in which tumour in front is, by careful manipulation, 

 to be detected*. 



When once Exostosis has formed, there seems hardly any 

 limit to its extension. Certainly, the higher it grows the worse in 

 its effects it becomes ; for then, not only are the cuneiform joints 

 rendered anchylosed by it, but that with the astragalus as well ; 

 nay, the very main joint of the hock itself is threatened with 



♦ See Plates II and III. 



