352 
SOME CLINICAL OBSERVATIONS. 
bridle. She is very restless to dress. In glancing at the poll, 
this region is the seat of a diffused tumefaction, more marked 
on the left than on the right, in which there exist two fistulous 
openings, reddish, situated near. the median line, towards the 
superior part, The diseased region is so painful that it is im¬ 
possible to explore it in the standing position, the animal fights 
too much. It is necessary to cast her. Then two fistulous tracts 
are found, running on each side of the cervical ligament, that 
of the left side a little higher than the right. From them es¬ 
capes a great quantity of thin, serous pus , exploration with 
various probes shows that the fistulse are sinuous. With the 
bistoury they are enlarged, and then explored with the finger; 
it is found that under the cord of the cervical ligament, between 
it and the atloido-occipital ligament, there is a large cavity, 
irregular, with granulating walls, containing unhealthy pus, 
mixed with mortified tissues. This cavity has developed in the 
fibro-elastic tissue situated between the two ligaments above 
named, and is formed at the expense of this tissue and of the 
serous bursa which assists the sliding of the cord of the cervical 
ligament over the atlas. The bursa is destroyed by the suppu¬ 
ration, which is itself sustained by the necrotic lesions of the sur¬ 
rounding tissues. These lesions have originated in the atloid 
hygroma, observed seven months ago, and also probably through 
some traumatism, such as violent rubbings, bruise or pressures, 
having injured the skin in its entire thickness, thus.opening an 
entrance to the pyogenic microbes. The case is evidently seri¬ 
ous on account of the length of time of its existence, its deep 
situation in a region whose anatomy is so complex and the move¬ 
ments so frequent, which will render the cicatrization difficult. 
And, again, it is known that, in that region, the necrosis has a 
tendency to spread, that the atloido-occipital can be destroyed, 
that purulent infiltrations may take place, afrd reach the verte¬ 
bral canal or in time give rise to septic or pysemic complica¬ 
tions. Observation has shown, however, that these dangerous 
complications can be prevented by section of the cord of the 
ligamentum nuchse. • With this operation, the constant pressure 
that it makes over the tissues underneath is removed, and there 
are chances for the inflammation to subside and for the entire 
elimination of the necrosed parts to take place ; in other words, 
for recovery. Accordingly, cervical deswiotomy is performe 
immediately. To this effect, the straight tenotomy knife is in¬ 
troduced, flatwise, in one of the wounds made in enlarging the 
fistula;; then the sharp edge of the instrument is turned against 
