148 
SPONTANEOUS LUXATION OF THE PATELLA. 
the purpose of keeping the bones in articulation. What the modus 
operancli of a blister may be in effecting this purpose, I cannot 
say, unless that, by its stimulus, the muscles be kept in a greater 
degree of tension. I do know, however, that luxation of this bone 
has not taken place after its employment in my practice ; on the 
contrary, where I have neglected it, displacement has recurred 
repeatedly, as the next case will exemplify, and which is my 
principal object in relating it. 
This last mare was tied up for a few days, and afterwards 
turned to grass without any renewal of the symptoms. The case 
I now allude to was of a bay gelding, four years old, that had 
been afflicted with influenza previous to having dislocation of the 
patella on the off side. A recapitulation of the symptoms, &c. will 
be unnecessary, as in all cases they are pretty much the same. 
Nor need I revert to the treatment, farther than that I did not re- 
sort to the blister in the first instance, the consequence of which 
was, that the bone slipped out of its place occasionally for several 
weeks afterwards, generally when about to start, or while working 
alongside of another : the coachman, however, had become so 
au fait at the mode of reducing it, that he required no assistance 
for that purpose, and the horse would resume his work immedi- 
ately, and without lameness. This being commonly the case, con- 
vinces me that no lesion of ligaments (although I do not deny but 
relaxation of them may exist) or other parts connected with the 
articulation of this joint could have taken place. In consequence 
of the repetition of the luxation I was obliged to blister. The 
horse w^ent to work one week afterwards, and no recurrence of the 
evil has taken place since. 
I do not think it impossible, from what I can glean concern- 
ing these cases in the human subject, that they may be of simi- 
lar origin, but it is treading on forbidden ground on my part 
even to suggest this. I should, however, be much pleased if 
any experienced member of that honourable profession — whose 
province it is — would condescend to give us his views as regards 
its probability. I am acquainted with the generally received 
opinions; but, as they differ materially from those offered in this 
article, and knowing no reason why the same circumstances should 
not produce the same results, where there is so trifling difference 
in the comparative anatomy of the parts, and believing the pre- 
disposing causes to be somewhat obscure, I trust I may not be 
considered presumptuous in making this humble request. 
