Section II. 



DISEASES OF THE SPINAL CORD. 



1. Acute Inflammation of the Membranes of the Spinal Cord. 

 Meningitis spinalis acuta. 



Under this term are inchided acute inflammations of the 

 membranes of the spinal cord which commence either in the 

 dura mater, the epidural tissues or the pia mater, and as a 

 rule, spread to the other membranes and even the spinal cord 

 itself, causing the production of a serous, sero-fibrinous, or 

 suppurative inflammatory exudate. 



Occurrence. Apart from cerebro-meningitis, the disease 

 is of rare occurrence in the domesticated animals, Imt among 

 tbem the majority of cases occur in the horse. 



Etiology. Inflammatory conditions of the membranes of 

 the spinal cord are always due to an infection. Now and then, 

 cases occur as a result of influenza, strangles, pyemia, or sep- 

 ticemia. Hess records a case of purulent meningitis of the 

 Cauda equina in an ox that was associated with purulent cere- 

 bral meningitis. Apart from some calcified tubercles in the 

 mediastinal gland and worm nodules in the small intestine, 

 there were no lesions in the internal organs. Injuries such 

 as blows on the vertebral column, docking the tail too short, 

 are sometimes causally connected with the disease, in that they 

 allow of the access of bacteria. Finally, in England, there is 

 a contagious disease of the sheep characterized by a pyemic 

 inflammation of the membranes of the cord which is known as 

 ''loping ill" (McFadyean). 



By Frohner, Cadeac and others distemper is thpujj^ht to he causally related 

 to an acute and clinically recogniyable spinal meningitis, because in this disease 

 there is an accumulation of a large (|uantity of clear liquid in the inter-meningeal 

 spaces (hydrorhachis). The authors have never observed any clinical evidence of 

 spinal meningitis in the many hundreds of cases of distemper that have come under 

 their notice. 



Not rarely the inflammatory processes spread to the mem- 

 branes from surrounding tissues. This is especially the case 

 in caries of a vertebra, the rupture of an abscess in the neigh- 



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