NAYICUL ARTHRITIS. 
547 
rupture of its superficial fibres has happened. At first, these fibres 
exhibit no more than partial disconnection or roughening ; gradu- 
ally, the entire surface becomes covered with elevations and de- 
pressions, and thoroughly uneven. And now very frequently 
may be perceived upon it red stjpyce , looking like muscular fibres, 
and these appear to be the result of exudation. Sometimes, in 
places, greenish spots are perceptible. The destruction of the ten- 
don proceeds with the continuance (and aggravation) of the dis- 
ease; extending from before backward, in spots, until at length 
the substance of the tendon becomes so reduced that it is actually 
transparent : nothing of it, on occasions, remaining save slender 
softened bundles of fibres, separated from one another. The rup- 
ture of these is the natural consequence of the ulcerative action ; 
though before that takes place, the tendon is found to have at- 
tached itself to a fresh place in the superior and posterior part of 
the navicular bone : the two parts being also united by a solid 
fibrous layer furnished by the right superior suspensory ligament, 
which is very much hypertrophied and thickened for the purpose.” 
The Terminations of Navicularthritis, then, may be 
looked for as follow : — 1. In resolution, or return of the navicular 
joint to its pristine condition — a termination, it is to be feared, not 
often to be looked for, even under favouring circumstances, and 
certainly never to be expected under opposite ones. 2. In adhe- 
sion, and this would appear to be the most common termination ; 
and though not the most favourable, still so far from being the most 
unfavourable that the horse will, in the absence of ulceration in the 
joint, probably step sound with it, or sufficiently so to continue his 
ordinary work. 3. In caries, ulceration of the bone, and in time 
liability to, if not actual, fracture of it ; with or without ulceration 
of the tendon as well, and in time liability to, if not actual rupture 
of it ; in either of which disastrous issues of the case nothing re- 
mains but the bullet. 
Collateral Disease, no doubt, will on occasions arise out of 
navicularthritis, though such is by no means so frequent as has 
been imagined : on the contrary, in the generality of cases, even 
for years will the disease confine itself to the navicular joint, and, 
as I said before, on occasions to the joint of one limb, the fellow 
fore-foot remaining unaffected. “With regard to ossification of 
the cartilages of the foot,” says Mr. Turner, “ and ossification of 
portions of the ligament of the navicular bone, and other bony ex- 
crescences within the foot, I have to remark, that, having dissected 
so many extreme cases of chronic foot lameness of many years’ 
standing, in which I have found all the ravages of the disease 
limited to a space within the foot not exceeding half-an-inch square, 
and unaccompanied with the slightest disease of any other part of 
