486 
PARALYSIS OF THE HIND EXTREMITIES. 
myelitis with formation of cavities in the spinal cord (syringomye- 
litis) and degenerative processes were met with at isolated points. In 
other varieties of paraplegia changes could doubtless be found in the 
spinal cord, provided examinations were made in advanced stages and 
by proper methods. Wolff saw the hind legs trailed in horses in conse¬ 
quence of fracture of the caudal vertebrae: here the change had clearly 
extended to the spinal cord from the point of fracture. On the other 
hand, it must be allowed that incomplete paraplegia is not always the 
result of primary disease of the cord, nor even of changes produced in 
it by infectious conditions (like influenza or strangles) ; it may also 
follow diseased processes in the vertebrae. In France, paraplegia is 
generally considered to result from injury to the spinal column in the 
dorsal or lumbar region, and is described, therefore, as vertebral dis¬ 
placement (entorse dorsolombaire). Yatel has given a thorough descrip¬ 
tion of the post-mortem of a horse affected with this disease. According 
to Pencil and Toussaint, the inter-vertebral discs in the dorsal or lumbar 
region sometimes appear yellowish-green and partly destroyed; in 
advanced stages they quite disappear, granulations form on the ends of 
the individual vertebrae, become adherent, ossify, and so lead to the 
formation of a synostosis. Sometimes exostoses form in the vertebral 
canal and press on the spinal cord. These changes may be associated 
with rupture of the muscles. Kigot states having found haemorrhages 
in the psoas muscles, and Goubaux abscesses in the longus colli. In 
these cases it certainly seems that the condition has been confused with 
other diseases. 
In horses, a condition simulating incomplete paralysis often occurs 
from catching cold, but disappears after a short time. In such cases 
muscular rheumatism is probably the cause. 
Periodic paralysis of the hind limbs, owing to obstruction of the 
blood-vessels of the thigh and pelvis, is not uncommon. Tumours may 
also develop in the vertebral canal or extend into it, press on the cord, 
and produce paraplegia. In a horse brought to the Alfort clinique, 
carcinomata were found to be pressing on the spinal cord and causing 
paralysis. Secondary carcinomata existed in the abdomen. Kamp- 
mann saw paraplegia in a foal from perforation of the second lumbar 
vertebra by a cyst which had discharged its contents into the vertebral 
canal. 
In cows, a condition which occurs during the last period of preg¬ 
nancy, but generally disappears after parturition, has been described as 
incomplete paraplegia. It is really due to insufficient muscular power 
to raise the greatly increased body load, and is favoured by advanced 
age, defective nutrition, very fat condition, or continuous confinement 
to the stable. In these animals, lesions in the spinal column and 
