936 PARALYSIS OF THE HIND LIMB. 



erf paralysis of the anterior branches caused by a neuroma. The 

 patient, a seven-year-old gelding, showed gradually advancing atrophy 

 of the gluteal muscles of the left side, which became so marked in 

 live months as to result in the bones being almost denuded of muscle 

 and appearing almost like an osteological preparation ; the muscles 

 of the thigh and lower thigh also suffered severely. At first there 

 was only insecure gait, but this symptom, always marked when the 

 hoist' was turned, gradually became aggravated. Finally the lower 

 part of the limb was kept permanently flexed, and, during forced 

 exercise, was slid along the ground and set down with a tapping, in- 

 secure movement. The backward portion of the stride was shortened. 

 On post-mortem examination a neuroma the size of a pigeon's egg 

 was found on the anterior gluteal nerve 4 inches from its point of 

 exit. 



Roloff described a similar case. Here, however, the horse became 

 lame suddenly, and carried the affected limb too near the middle 

 line, as well as extending it too far forwards. In time the muscles 

 of the quarter wasted to a great extent. It seems probable, however, 

 that in this case the posterior gluteal nerves were paralysed, as 

 suggested by the abnormal adduction of the limb. 



B. Paralysis in the region supplied by the great sciatic nerve. 



Paralysis of the great sciatic nerve. 



Paralysis of this nerve has been observed in horses and dogs. 

 The causes are : lesions in the course of the nerves, or disease of the 

 spinal cord or brain. Disease of the spinal cord usually produces 

 double-sided paralysis. In horses sciatic paralysis may result from 

 falling on the haunches, slipping in heavy draught, forced extension 

 of the hind limbs, compression of the nerve by tumours, or exostoses, 

 or from systemic infection ; in dogs the usual causes are falling 

 from a height, severe bruising of the hind-quarters, and neuritis 

 following distemper. Albert found, on post-mortem examination 

 of a horse which had been treated for three months without effect, 

 the residuum of a blood extravasation surrounding the nerve at the 

 point where it left the pelvic cavity. The tissues below this point 

 were atrophied, and the muscles, especially the M. rectus femoris, 

 had undergone extensive fatty degeneration. 



In addition, paraplegia is by no means uncommon in dogs, and 

 even in horses ; in the hind limb the great sciatic nerve is affected, 

 and in the opposite fore limb the axillary plexus. Such cases are 

 clearly of cerebral origin. The condition described by Beel as 

 paralysis of the hip nerves appears to have been paraplegia. Friis 

 saw paralysis of the right fore and left hind limbs, which was not 



