488 
PARALYSIS OF THE HIND EXTREMITIES. 
of continuity in the spinal cord occurs behind the exit of the nerve 
referred to (fourth to sixth lumbar vertebrae). The same peculiarity also 
occurs in fracture of the spinal column in the dorsal region, as has 
been noted in horses. Dogs sometimes learn to walk on the fore legs, 
as related by Nocard ; they lift the hind-quarters into the air by power¬ 
fully contracting the longissimus dor si, &c., after the manner of circus 
dogs. 
(2) Reflex irritability is completely in abeyance, and the animals 
make no resistance to the operator’s manipulations. This is always the 
case where the seat of disease is in or behind the lumbar portion of the 
cord. When in front of this spot, that is, in the dorsal region or 
further forward, reflex irritability is not only retained, but may often 
be abnormally pronounced, so that stimulation of the skin, ligaments, 
or bones (slight blows or pricks with the needle) cause active contrac¬ 
tions in the paralysed muscles. Continuous contraction (cramp) may 
thus be caused (spastic paralysis). Nocard saw increase of the tendon 
reflexes in a dog. 
(8) In grave lesions of the cord, sensibility appears to be completely 
lost; in myelitis spinalis it is at first not much impaired; its continu¬ 
ance points to injury of the posterior columns and of the grey posterior 
cornua. In pressure paralysis, sensibility may sometimes be increased, 
as shown by Nocard’s reported cases in dogs ; movement of the paralysed 
hind-quarter produced acute pain (paraplegia dolorosa). The examina¬ 
tion of large animals is more difficult, because sensation cannot be 
exactly gauged, reflex movements being so difficult to distinguish from 
those caused by painful sensations. 
(4) To the above cardinal symptoms of paraplegia are added those of 
paralysis of the bladder, rectum, and tail (see “ Diseases of the Tail ”). 
There is often incontinence of urine, and heces cannot be discharged 
without assistance. This grouping of symptoms generally accompanies 
pressure paralysis from fractures of vertebrae or of the sacrum, from 
extravasation of blood into the vertebral canal, and in rarer instances 
from tumours, but may also occur in concussion of the spinal cord. The 
diagnosis must be based on the history of the case, its manner of origin 
and course. In fractures of the vertebrae, displacement of fragments or 
crepitation may be detected. 
The symptoms of incomplete paralysis show still greater variety; 
but even though it is not possible, in every case, to form an accurate 
diagnosis, it is well, from the clinical standpoint, to distinguish two 
kinds :— 
(1) Paraplegia incompleta vera, vel spinalis (true incomplete or spinal 
paralysis); and 
(2) Par. incompleta spuria (incomplete spurious paraplegia). The 
