372 HOCK LAMENESS AND FRACTURE OF TI1E TIBIA. 
which she was unshackled and allowed to rise, which she readily 
did. But, as soon as she was up, and caused to move, 1 instantly 
made the observation that her thigh was fractured. On closer ex- 
amination the fracture could be detected at the inferior end of the 
tibia. Shortly afterwards I waited upon the owner to inform him 
of what had happened, and the circumstances under which it oc- 
curred. As the best course that could be adopted, I advised her 
destruction. The first question that arose was, how did the frac- 
ture occur ] The second, when did it take place 1 The conclusion 
I arrived at, and the opinion I expressed to the owner before she 
was destroyed, was, that the fracture had been in existence for 
several days, although the parts had not become displaced until she 
was cast for the operation. 1 felt no hesitation in asserting that I 
believed it might have been caused during the night previous to 
my examining her, probably either by lying down or getting up, 
seeing she had lain down that night, a thing she had not done for 
several nights previously. She had performed her usual work in 
an omnibus the evening previous to my seeing her. The horse- 
keeper informed me that she had been very nearly as lame in the 
near limb for a week past. I made a very careful examination, but 
did not for one moment suspect a fracture. 
Post-mortem examination shewed an oblique comminuted 
fracture of the tibia in the off limb, extending across the whole 
length of the inner groove of the inferior articulation of that bone, 
and upwards throughout the body of it, eight and a-half inches in 
length. The synovial membrane covering the surface of the inner 
groove, and likewise the ridge between the grooves, were highly 
inflamed, and of a purple appearance. The synovial membrane of 
the astragalus was slightly involved. The texture of the bone, 
commencing from the inferior articulation, extending into the body 
of it for about an inch, was extensively diseased, and softened in 
structure. I examined the hock and tibia of the near limb with a 
view of finding the cause of the extreme lameness which had been 
present in it. The hock exhibited a small spavin ; but the tibia 
presented in every respect, excepting the fracture, the disease as 
described in the tibia of the opposite limb, only in a severer form. 
In fact, ulceration had commenced its work both on the lower sur- 
face of the tibia and also on the corresponding articulation of the 
astragalus. There was, extending across the inner groove of the 
tibia, a line into which I could easily press a scalpel to the depth 
of an eighth of an inch. Upon the outside of the bone could be 
traced a crack, commencing from the articulation and extending 
upwards, for the space of two inches, evidently exhibiting a strong 
disposition to fracture in this bone. Upon the outer surface of it, 
and contiguous to the crack, Nature had commenced throwing out 
