WOUNDS OF THE ARTICULATIONS. 
35 
which synovia escapes. This is accounted for by the posi- 
tion of some synovial sheaths, which become extended over 
the folds of the nearest ligaments and fibro-cartilaginous 
structures, thus giving to them a great extent of surface. 
In some parts the synovial membrane is merely sub-cuta- 
neous, and this peculiarity exists particularly in the neigh- 
bourhood of ball and socket joints, and the shoulder. 
The veterinary surgeon is very often called upon to treat 
articular wounds in the horse ; it is, in fact, the monodactyles 
which are the most exposed to these lesions, in consequence 
of the active service required of them. 
Cases of this kind are rarely met with in ruminants, as the 
proprietors instead of consulting a veterinary surgeon, have 
them destroyed. 
Causes. — Articular wounds are produced in various ways, 
principally, however, by pointed and cutting instruments, or 
by contusions. 
A pointed instrument may penetrate an articulation, 
although accidents of this nature are rarely met with, if we 
except nails, which occasionally enter the foot whilst horses 
are going through the streets. Frequently the name of open 
joint is given to lesion of the bursa of the navicular bone, 
which may exist without the articulation of the last phalange 
being implicated. 
Some operations, also, especially those where the cartilages 
of the foot are removed, occasionally produce articular 
wounds. Iodine injections, combined with puncture, in the 
treatment of hydrarthrosis, according to report, often occa- 
sion results of a very serious nature. 
These wounds are likewise frequently caused by contu- 
sions ; such as blows on the foot, the knee, the elbow, and 
the hock. Diseases of the coronet often lead to wounds of 
the articulation of the foot, especially during winter, when 
the. shoes have large and high caulkings. Other causes may 
be mentioned, but the most frequent are those above named. 
The knees of horses are often severely wounded by their 
falling on sharp stones ; the same cause will produce acci- 
dents of a similar nature of the pastern, and abrasion or 
destruction of the tissues may then lead to exposure of the 
articular surfaces. I have seen in a mule a wound pene- 
trating the articulation of the lower maxillary bone, caused 
by the application of a splint invented by Gohier to remedy 
partial luxation of the cervical vertebrae. 
Lastly, firing, which is frequently resorted to for diseases of 
the articulations, when incautiously done, often occasions 
deep wounds from which the synovia escapes. 
