l'RACTURE OP THE SESAMOID BONE. 1G5 
the unfavorable state of the animal, consented to have him 
destroyed, which I did with hydrocyanic acid. 
The following morning I made a post-mortem examination, 
first removing the off shoulder and the ribs on that side. 
On tracing the intestines, nothing abnormal was met with 
until arriving at the colon, where about five inches of that 
bowel had protruded through a rupture of the mesocolon two 
inches in width ; there was only a slight blush of inflamma¬ 
tion in the protruded part. Anterior to it the ingesta was 
very liquid ; posteriorly, the pellets were hard and entire. 
The near kidney was highly congested, the other not. The 
heart was large, but healthy, as also the liver ; the lungs bore 
traces of the poison given. 
On removing about eighteen inches of the spinal cord 
contained in the dorso-lumbar vertebras, I found the enve¬ 
loping membranes much congested, but not the substance of 
the cord itself involved. Examining the near fore leg, I 
found the suspensory ligaments, the perforans and perforatus 
tendons, perfectly healthy. The capsular ligament sur¬ 
rounding the pastern-joint was thickened to about three 
times its normal state; the outer sesamoid bone was entire, 
but the inner one was broken into five irregular pieces. 
The structure of the bone was entirely changed, and the 
whole articular surface, with the exception of a small portion 
about the size of a pea, destroyed. The surfaces made by 
the fracture showed marks of slight attrition, and were much 
denser than the bodies (if we may use the term) of the parts 
not exposed to this trifling motion. No portion was in the 
least displaced, separation not taking place until the liga¬ 
mentous connections had been removed. The articular 
surfaces of the pastern-joint contained some small grooves 
from before backwards, as though grit had been introduced, 
but these appearances were obliterated in boiling. The 
pedal bone was very spongy, and had ossification of its inner 
lateral cartilage. 
Having thus far described the case, let us inquire when 
the sesamoid bone was broken. My opinion is that it 
occurred when the horse struck against the turnip; and the 
bone being broken in such a manner that no bony spiculae 
were detached to work through the surrounding parts, and 
crepitus being prevented by the powerful force of the en¬ 
circling structures, will account for the mischief not being- 
discovered during the animal's lifetime. Again, if the 
fracture had not taken place until after the exfoliation of the 
bone, then the broken edges would have been equally soft 
with the other parts. 
