OPEN SYNOVIAL CAVITIES. 413 
the shoulder, has been opened by the animal drawing a vehicle being 
run into; or by the horse running away and coming in contact with 
some obstacle. Any synovial cavity within the body may be penetrated 
by an unfortunate combination of circumstances; or by the unbridled 
passion of the groom, who may have a pitchfork near at hand. So 
also they have been cut into by the arrogance of unskillful operators. 
However, it matters not how the misfortune may arise, the mode of 
treatment and the manner of cure is in all such cases exactly the same. 
Neither, as regards the primary effect, is it of subsequent importance 
whether air be admitted into an opened bursa or sac, a synovial sheath, 
or the interior of a joint. All of these structures are formed into blad- 
ders or closed cavities. They all contain a similar secretion, which is a 
transparent, albuminous fluid, resembling white of egg. They all are 
of one use, or all serve to facilitate motion. The bursa is the smallest; 
the synovial sheath is the next in magnitude; and joints may be much 
the largest. The secondary effects are proportioned to their size, but 
in the first instance much constitutional disturbance will attend the 
opening of each. 
These structures are not formed to endure the presence of atmosphere ; 
air is admitted a short time after each displays inflammation. This 
creates symptoms of irritability, and air will enter before we see the 
wound. The secondary effect is, however, most to be dreaded. Burse 
are small bladders, or closed sacs, distributed over the body, and located 
wherever the natural motions possibly might originate friction. Sheaths 
always embrace tendons, being essentially closed sacs. The secondary 
effects of tendinous sheaths are so much the more to be dreaded than 
those attending punctured burse, because the last generally lie loosely 
between highly-organized parts; whereas a sheath is partly fixed upon 
a tendon, and tendon, being lowly organized, is more difficult to cure 
when it is diseased. However, joints are much worse than the preceding 
two; because in these the synovial membrane is partly spread over the 
cartilage, which lies upon the articular surfaces of bones. Now, carti- 
lage is the most lowly organized substance in the entire body. When 
disease fixes upon it the morbid condition is so slow, so irritating, and 
so difficult to eradicate, that science almost despairs of the issue. 
The results indicated show that every effort should be made to ward 
off the secondary effect. Therefore, when an accident of this nature 
occurs, proceed with the utmost gentleness. Having procured a large 
sponge and a pail of milk-warm water, saturate the sponge and squeeze 
it dry, above the injury. Do not touch the sore, but allow the fluid, as 
it gravitates, to wash off all or any foreign matter. With regard to 
the wound, dirt seldom enters that. When it does, the suppuration which 
