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VETERINARY SURGICAL OPERATIONS 



due to a causative lesion as uniform as the symptom itself, 

 were it only known. To claim that one case is due to chorea, 

 — a brain lesion, — another to some defect in the spinal cord, 

 another to some abnormality of a peripheral nerve, another 

 to injury to the stifle, another to spavin, another to side- 

 bone, another to injury to the extensor tendons, and another 

 to contraction of the tibial fascia, seems very illogical when 

 the uniformity of the symptom is taken into consideration. 

 At the present time stringhalt is not undestood. It is a 

 mysterious manifestation of some unknown lesion. Its treat- 

 ment is empirical. It is sometimes cured by dividing the 

 peroneus tendon, but the mechanism by which the cure is ac- 

 complished is quite as mysterious as the primary lesion it- 

 self. The peroneus is an accessory extensor; it has no 



Figs. 114 and 115— Two Distinct Forms of Operable Stringhalt. 



marked action upon the hock, and its chief mission is to 

 assist the extensor pedis to extend the phalangeal articula- 

 tions. If divided accidentally or surgically its loss produces 

 no perceptible change in locomotion, which fact shows con- 

 clusively that the cure from tenotomy is not due to any di- 

 rect modification of muscular activity. The same fact proves 

 also that stringhalt is not of nervous origin. The cure of 

 some cases by peroneal tenotomy points to a lesion some- 

 where near the peroneus muscle, at its origin, its belly or its 

 tendon. That the lesion is sometimes located near its origin 

 is suggested by the cures which follow division of the in- 

 ternal patellar ligament. These two operations may sooner 

 or later solve the perplexing problem; and in view of all 

 facts connected therewith it will not be surprising if the 

 cause is found somewhere in the neighborhood of the stifle, 



