SLOW COMPRESSION OF SPINAL CORD. PARALYSIS. 



Causes : Caries, vertebral diseases and lesions, neoplasms, actinomycosis, 

 tubercle, abscess, organizing exudates, parasites. Melanoma, cholesteatoma, 

 sarcoma, papilloma, lipoma, glioma, chrondroma. Symptoms : advance 

 insensibly, or by sudden leap with exudate, spasm, paresis, transverse, senses 

 clear, muscular atrophy, advance from behind forward. Cervical, dorsal, 

 lumbar lesions. Bladder, sphincters, tail. Symptoms increased by move- 

 ment. Treatment : according to lesion. Tumors, hopeless. Blood clots, 

 Actinomycosis. Analgesics. Electricity. 



Causes. Slowly progres.sive compression of the cord has been 

 already noted as resulting from caries and other disea.ses of the 

 vertebrae. It remains to notice stich as result from the growth 

 of tumors and other neoplasms in the spinal canal. In the horse 

 these are commonly melanoma (in white horses), sarcoma, en- 

 cephaloid, papilloma, cholesteatoma, and osteoma ; in cattle, 

 beside tubercle and actinomycosis, have been found sarcoma, 

 lipoma, osteoma and glioma ; and in dogs sarcoma and chon- 

 dro-sarcoma. Chronic ab.scesses may be met with in all ani- 

 mals determining the same class of symptoms by slow pressure. 

 In the same manner exudates in process of organization contract, 

 and are liable to compress the myelon. Cadeac draws attention 

 to a calcic degeneration of exudates in the dura mater of the dog 

 (o.ssifying pachymeningitis), and of ossification of the inter- 

 vertebrse cartilages with vegetations on their surfaces. Para.sites 

 also exercise a growing pressure, especially echinococcus, in 

 cattle cysticercus mediocanellata, in sheep and dogs coenurus, 

 and in pigs and dogs cysticercus cellulo.sa. 



Melanoma. In gray and white horses, with dis.seminated 

 melanosis, the spinal canal is often involved, the pigmentary sar- 

 coma appearing in small formations and sometimes large enough 

 to determine injurious pressure. In the early stages these may 

 cause .stiffness and lameness referable to particular muscles or 

 groups, varying in situation, even as to the limbs affected, at 

 successive dates, and finall}^ merging into paraplegia. 



Cholesteatoma is less common than in the encephalon, yet 

 one is reported by Dexler as attached to the pia mater and pos- 

 sessed of great firmness, crisply crackling under the knife. It 

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