SPAVIN. 
729 
the joint. When the articular surfaces have undergone change and the 
cartilage is destroyed, repair is absolutely impossible, and recovery can 
only result from adhesion of the opposing diseased articular surfaces. 
This takes from six to eight weeks, but may be indefinitely prolonged ; 
sometimes it never occurs, and the lameness is incurable. In actual 
practice it is never possible to foretell with certainty how the case will 
terminate, though a careful consideration of all the facts may give some 
indication. 
Though union principally depends on the animal being rested and 
placed under treatment, failing which the parts seldom unite, and 
lameness persists, the converse is not equally true, for even the most 
energetic treatment is not always successful. Resolution, i.e., the 
disappearance of inflammation and local change, is exceptionally rare. 
Errors in diagnosis have led to the belief that absorption often occurs, 
and that absorptive processes may be assisted by treatment. Holler’s 
experience is quite opposed to this view, which is due to confusing with 
spavin (i.e., arthritis chronica) many varied disease processes, the sole 
common feature of which is lameness. It is certainly difficult at times 
to confidently diagnose spavin on the first examination, especially if no 
reliable history is available. Nevertheless, an attempt at distinction 
should always be made, otherwise prognosis and treatment are mere 
gropings in the dark. 
Not infrequently lameness diminishes or disappears after a long rest, 
but the improvement is only temporary, and as soon as the horse returns 
to work, lameness recurs in an even severer form. It is clear that, with 
rest, the inflammation may diminish in intensity, but it seldom dis¬ 
appears completely. Though spavin may be viewed as a typical disease 
of the hock-joint, yet it shows many variations in course, partly on 
account of the conformation of the joint, partly of the degree and extent 
of disease processes, but especially of the variation in external influences, 
amongst the principal of which must be ranked the treatment employed 
in the particular case. 
In forming a prognosis it is necessary to bear in mind all the factors 
which favour relative recovery, i.e., which contribute to removal of lame¬ 
ness, as well as those, on the other hand, which are likely to prevent it. 
Such factors comprise :— 
(1) The work required of the animal. The greater the exertion, and 
consequently the strain on the hock-joint, the less the chance of 
permanent recovery. Heavy cart-horses and hacks are therefore 
unfavourable subjects. 
(2) The degree of lameness and the time it has existed. If, in spite 
of proper treatment, lameness persists, it shows that the conditions are 
unfavourable to anchylosis, and the chance of recovery, therefore, is 
