938 



PARALYSIS OF THE HIND LIMB. 



throughout Germany, large numbers of dogs are employed for 

 drawing light carts, sometimes singly, sometimes in pairs. They are 

 of no determinate breed, and vary from the size of a collie up to that 

 of a boar-hound.) In one case the dog had fallen from a window, 

 and at iirst showed complete paraplegia, which, however, disappeared 

 after .1 lew days, leaving one limb affected with sciatic lameness, which 

 also disappeared soon afterwards. The second dog became affected 

 during convalescence from distemper, and in the third the lameness 



had no apparent cause. 



Moller has seen and described one 

 case of paralysis of the internal popliteal 

 nerve. In this disease the muscles lying 

 at the posterior surface of the tibia are 

 affected ; plantar flexion is impossible, 

 that is to say, the hock cannot be 

 extended nor the foot flexed (in the 

 plantar sense). As, however, in the 

 horse flexion of the hock brings both 

 flexors of the foot, and especially the 

 tendon of the flexor pedis perforans, 

 into tension, the phalanges are, in this 

 lameness, necessarily fixed in a position 

 of plantar flexion. This is especially 

 noticeable when the animal stands on 

 the paralysed limb, because the hock 

 is then excessively flexed. It is still 

 possible, however, to place weight on 

 the limb, because the Achilles tendon 

 fixes the hock. 



The limb is advanced with all the 

 joints excessively flexed, the foot being 

 lifted very high, and set down with a 

 hesitating (''tapping") movement; the action as a whole bearing 

 some resemblance to stringhalt. The condition is clearly due to 

 paralysis of the muscles at the back of the lower thigh. The gas- 

 trocnemii arc unable to extend the hock, whilst the flexor metatarsi 

 is passive, and only affects movement through the medium of its 

 peculiar tendinous apparatus (see " Rupture of the Flexor Metatarsi"). 

 Trotting is impossible. 



The muscles at the posterior surface of the thigh, particularly the 

 gastrocnemii and flexor pedis perforans, are relaxed, and afterwards 

 become atrophied. Paralysis in this case appears to have been due to 



FlO. 522. - Paralysis of internal 

 popliteal nerve. 



