472 
CURVATURE OF THE SPINE. 
may also bo responsible for spinal curvature, but as the animals are 
usually killed, such cases seldom have an opportunity to develop. Finally, 
disease of the intra-vertebral discs may cause deformity. 
A twenty-five year old horse which had suffered for many years, and in 
increasing degree, from hollow-back was found on post-mortem to have 
marked convexity of the spine, extending as far as the third lumbar vertebra. 
The aorta, which was aneurysmal and had very thin walls, followed this curva¬ 
ture ; the articulation between the last lumbar vertebra and the sacrum showed 
signs of arthritis. The centres of the intra-vertebral cartilages, between the 
dorsal and lumbar vertebrae, had disappeared; their circumferences were 
ossified, and exostoses existed both in the vertebral canal and on the under 
surface of the bones. The superior spinous processes of the dorsal vertebrae 
also showed signs of rarefying ostitis, which had diminished movement. The 
bodies of the lumbar vertebrae were firmly united by bony material. 
Symptoms and course. Only when the above described changes 
become greatly developed do they excite attention. The rate of develop¬ 
ment of lordosis is very varied. When it appears suddenly it may be 
followed by difficulty in respiration. As a rule, however, it occurs 
gradually, and only in exceptional cases becomes so well marked as 
to interfere with the animal’s usefulness. Most of the dorsal and 
lumbar vertebrae are usually involved in the curvature. Where single 
vertebrae are diseased, e.g., where the deformity is due to caries, flexion 
develops slowly, whereas that resulting from fracture is of sudden onset. 
This fact generally enables the nature of the disease to be distinguished. 
Treatment. In animals reduction of displaced vertebrae is seldom 
possible. The only means (orthopaedia) is difficult and tedious, so that 
results are robbed of their value by the time and expense involved. 
Prophylaxis is more important, especially in foals. Up to a certain 
point lordosis can be prevented, by proper precautions. Young horses 
with long backs should never be heavily loaded. It is best to give con¬ 
centrated food, and to place it in low mangers or on the earth. Grazing 
exercises a beneficial influence, on account of the back having to be bent 
upwards as the animal crops the grass. 
IY.—FRACTURE OF THE PELVIS. 
Fracture of the pelvis is commonest in the larger animals, particularly 
in horses, and is caused by falls on smooth pavements, by collisions, 
sometimes by the animal’s legs slipping from under it, or by the horse 
making a sudden turn when being ridden. Since asphalt has been 
extensively laid down fractures of the pelvis in horses have greatly 
increased in frequency, and often occur even without the animal fall¬ 
ing. Trasbot saw fracture of the ilium in a race-horse produced while 
galloping. The pelvis may also be fractured by casting the horse on 
hard ground, if the pelvis falls first; the animal’s chest should first touch 
