SPONTANEOUS LUXATION OF THE PATELLA. 
147 
these cases was the animal low in flesh, but in that state of debi- 
lity which is generally the effect of disease and want of exercise. 
One of these animals had been similarly affected about twelve 
months previous to this. I will briefly relate two of these cases, 
as some circumstances connected with them appear to substantiate 
my views: — 
A grey mare, four years old, the property of W. Phipson, Esq., 
of Edgbaston, had, after becoming perfectly sound of a punctured 
foot, been turned to grass, having on the previous day had her head 
loosed after being tied up in consequence of her fore foot being 
blistered. The coachman came to me in the morning, and de- 
scribed her as being fixed in the field as if one of her hind legs 
were fastened to the ground, and, to use the man’s own words, 
it was “ more like a post than a leg,” and she was “ sweating 
uncommonly.” I had no doubt of the nature of the case. When 
in attendance, I found the mare precisely as she had been described 
to me. I requested the groom to take hold of the leg between 
the hock and the fetlock, and draw it forward, at the same time 
placing the palm of my hand upon the patella, which in these cases 
is always* dislocated outwardly, and, by employing steady pressure 
in the direction of the joint, I reduced it without difficulty. I then 
kept my hand upon it to retain it in its place while she was 
being led to her stable, about one hundred yards distant, and 
found that, as 1 have done in most cases (immediately after the re- 
duction of this bone), as soon as the muscles inserted into it were 
brought into action, and almost before the foot was off the ground, 
if it were not from this precaution being employed, it would again 
slip from its articulation, as though the muscles, in consequence 
of the previous displacement of the bone, acted in a direction 
favourable to this end. I caused her to be secured by the head, 
and so placed her that as little lateral motion as possible could be 
made, since this movement or turning round towards the side 
affected is very apt to displace the bone again. I afterwards 
directed the groom to place his hand in the proper situation upon 
the bone, in order to retain it in its place for a few hours. The 
next morning I called to see her, and found her all right, though 
I was informed by the groom that when he first saw her in the 
morning she was fixed as on the day before, but by pushing 
her on one side to get to her head the bone suddenly “ went into 
its place again.” From this time it remained in its situation. 
I blistered over the joint, which is my common practice ; at first 
employed, it is true, more with the view of relieving, by counter- 
irritation, any injury that the joint might have received, than for 
Mr. Cherry’s case throws a doubt upon this. — E d. 
