ment
affects old horses more frequently than it does young and is seen in all
breeds of animals including mules.

[Illustration: Fig. 52--Spring-halt.]

Symptomatology.--This disease develops slowly, and progressively
increases in severity as a rule, but does not ordinarily constitute
cause for rendering an animal unserviceable. While the affection is
sometimes bilateral (occasionally affections of the forelegs are
reported) and the extreme flexion of the legs in the spasmodic manner
which characterizes spring-halt, cause great waste of energy during
locomotion, yet such cases are rare. Usually the ailment is markedly
evinced when subjects are first taken from the stable, but as they are
exercised the manifestation diminishes, and in many instances it
completely subsides. The condition is generally more noticeable when the
subject is made to step backward. In some animals there is marked
abduction at the time flexion occurs and in singular instances the
spasmodic contraction is so violent that the subject falls to the ground
as a result of the peculiar flexion of the leg.

In severe cases of "scratches" or chemical irritation of the extremity,
the legs are abnormally flexed in a manner which simulates spring-halt,
but because of the evident injury of the parts this is not likely to
confuse. Since all facts concerning etiological agencies are surrounded
with so much obscurity, classification does not lend any particular
assistance in the consideration of this ailment.

Prognosis.--One cannot intelligently give a prognosis in these cases
if forecast is expected to state the exact course following treatment.
However, in a general way, cases of recent affection are thought more
favorable than are those of long standing or in old animals where
myositis and other muscular and fascial affections exist owing to years
of hard service.

Treatment.--No known line of medicinal treatment is of service, nor is
any particular surgical operation to be considered dependable for
obtaining relief. Operations of almost every conceivable nature have
been tried with the hope of securing recovery in spring-halt but under
no condition can the practitioner as yet be reasonably certain of
effecting permanent relief in any case. Treatment is, therefore,
entirely empirical.

Neurectomies have been performed and recoveries following were
attributed thereto; fascial divisions in the crural region have been
done with good results and this man