1026 DISEASES OF THE HOCK. 



asepsis being almost impossible. The result is doubtful; cases are 

 said to have been cured, though in one, which was successful, the 

 incision was only carried through the skin on account of bleeding. 



Bassi suggests dividing the internal lateral ligament of the patella. 

 Experiments show that this operation is not easy, on account of the 

 ligament in question being so ill-defined. The method is worth a 

 trial in cases where the cause is thought to lie in the stifle-joint. 



Starting from the hypothesis that in one case stringhalt was 

 produced by inflammation of sensory nerves, Moller divided the 

 anterior tibial nerve, but without success. Failure also followed 

 subcutaneous injections of morphine and veratrin, and section of 

 the internal insertion of the flexor metatarsi muscle. Section of 

 the posterior tibial nerve above the hock has succeeded in cases where 

 the cause of the disease was situated in the lower portion of the limb. 

 On an animal affected with bilateral stringhalt, Cadiot successively 

 performed section of the anterior tibial nerve, the peroneus tendon, 

 the plantar nerves and the cord of the flexor metatarsi, without 

 noticeable improvement. In another case he divided the great 

 sciatic nerve at the lower third of the leg ; in four days its function 

 was normal, but a month later the hoof sloughed and the patient 

 was destroyed. 



A condition in some respects resembling stringhalt has been 

 called " straw cramp." The animals while standing on straw 

 show peculiar symptoms, particularly when turning round. The 

 affected hind limb appears momentarily fixed to the ground, then 

 suddenly lifted as in stringhalt. Painful conditions like inflammation 

 in the skin of the heel or in the bend of the hock produce similar 

 symptoms, which are then, of course, easily explained. But in 

 some horses, particularly in ponies, the attacks occur without any 

 visible cause. The most careful examination fails to detect pain in 

 the affected limb. In such cases tibial neurectomy produces no 

 particular improvement. Similar symptoms are seen in upward 

 luxation of the patella, and in certain debilitating diseases. 



In a horse Moller had under observation, a similar effect was 

 produced by irritation of the ear. If the finger were introduced 

 into either ear, the hind limb of the same side was lifted and carried 

 forward in an almost horizontal direction, the movement being 

 convulsive. Though the condition only lasted a few seconds, the 

 horse was quite useless, because the pressure of the bridle or halter 

 on the ear immediately induced fresh attacks. Not the slightest 

 anatomical change could be detected in the ears. 



