course, sometimes
result from such a cause as a badly prepared bed, or the accidental
presence of a hard body concealed in the straw, or to a heavy fall when
the movements of the patient have not been sufficiently controlled by an
effective apparatus and its skillful adaptation, but it is quite as
liable to be caused by the violent resistance and the consequent
powerful muscular contraction by the frightened patient. The simple fact
of the overarching of the vertebral column, with excessive pressure
against it from the intestinal mass, owing to the spasmodic action of
the abdominal muscles, may account for it, and so also may the struggles
of the animal to escape from the restraint of the hobbles while frantic
under the pain of an operation without anesthesia. In these cases the
fracture usually occurs in the body or the annular part, or both, of the
posterior dorsal or the anterior lumbar vertebra. When the transverse
processes of the last-named bones are injured, it is probably in
consequence of the heavy concussion incident to striking the ground when
cast. The diagnosis of a fracture of the body of a vertebra is not
always easy, especially when quite recent, and more especially when
there is no accompanying displacement.

_Symptoms._--There are certain peculiar signs accompanying the
occurrence of the accident while an operation is in progress which
should at once excite the suspicion of the surgeon. In the midst of a
violent struggle the patient becomes suddenly quiet; the movement of a
sharp instrument, which at first excited his resistance, fails to give
rise to any further evidence of sensation; perhaps a general trembling,
lasting for a few minutes, will follow, succeeded by a cold, profuse
perspiration, particularly between the hind legs, and frequently there
will be micturition and defecation. Careful examination of the vertebral
column may then detect a slight depression or irregularity in the
direction of the spine, and there may be a diminution or loss of
sensation in the posterior part of the trunk, while the anterior portion
continues to be as sensitive as before. In making an attempt to get upon
his feet, however, upon the removal of the hobbles, only the fore part
of the body will respond to the effort, a degree of paraplegia being
present, and while the head, neck, and fore part of the body will be
raised, the hind quarters and hind legs will remain inert. The animal
may perhaps succeed in rising and