Prognosis.--Spontaneous recoveries occur and such cases are reported by Bouley who is quoted by Cadiot as having observed division of the tendo Achillis due to a sword wound wherein at the end of four months recovery was complete. Division of this tendon in brood mares has been practiced by the early settlers of parts of the United States for the purpose of preventing their straying too far from home. In such instances one leg only was so mutilated and in most instances, it is reported that spontaneous recovery took place. In unilateral involvement without complications, the prognosis is not unfavorable if provisions for giving necessary attention are available. Treatment.--The subject is to be confined in a sling and the member bandaged and supported by means of leather splints. Immobilization as for fracture is not necessary but, nevertheless, movement is to be restricted as much as possible. In case of open wounds, the exposed tissues are cared for along general surgical lines. Where the divided parts of the tendon are maintained in fairly close and constant relation, granulation of tissue, sufficient to sustain weight takes place in from six weeks to three months. Spring-Halt. (String-Halt.) Occurrence.--This condition is a myoclonic affection of the hind leg which is discussed in works on theory and practice under the head of neuroses, but the cause or causes have not been established. Theories that heredity is responsible have their supporters and advocates of hypotheses attributing it to disease of the sciatic nerve, patellar subluxation, fascial contraction of various muscles, "dry spavin" (tarsal arthritis), iliac exostoses, disease of the foot and contraction of the hoof, are on record in veterinary literature. This ailment 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.