Diagnosis. 711 



Diagnosis. Diagnosis is associated with little or no diffi- 

 culty in cases in which there are the following symptoms : very 

 slowly progressive paraparesis and para-anesthesia, local 

 swelling and pain of the vertebral colmnn, evidence of spon- 

 taneous pain, a girdle-like area that is hyperesthetic, and dis- 

 turbances of micturition and defecation. An error of diagno- 

 sis is far more likely to be made in those cases in which the 

 paralysis appears to set in or actually sets in suddenly. The 

 presence of more or less pronounced atrophy of the muscles 

 and spastic movements of the paralyzed portion of the body 

 lead one to suspect that certain motor disturbances have been 

 in existence for some time. Possibly also there is a history 

 of the occurrence of rheumatic pains and stiffness of gait. 



The points that are of importance in the differential diag- 

 nosis of compression of the cord, ossifying meningitis, contu- 

 sion of the cord, and myelitis, have already been dealt with 

 under these diseases. Muscular rheumatism with which the 

 disease may be confused owing to the evidence of pam, is 

 easily distingaiished by the facts that there is no loss of mus- 

 cular power," rigidity of the muscles is absent, the sensibility 

 of the skin is increased and the reflexes are normal. In the 

 horse, thrombosis of the branches of the posterior aorta might 

 be confused with the disease, but this is distinguished by the 

 fact that the paralysis which is observed during movement 

 rapidly disappears when the animal is left at rest, and rectal 

 examination enables one to establish the diagnosis. 



The seat of the compression can only be determined accu- 

 rately in cases in which there is some distortion of the body; 

 there is local pain of the vertebrae, a hyperesthetic zone can 

 be demonstrated, the extent of the paralysis and loss ot sen- 

 sation, the condition of the reflexes, and the functions ot the 

 bladder and rectum also afford information. In other cases 

 one can do no more than determine the approximate seat ot 

 the lesion, and in some cases this amounts only to deciding that 

 it is situated in the cervical, dorsal, lumbar or sacral sections 

 of the spine. 



The cause of the compression can m some rare cases be 

 accurately determined. In this connection, the following points 

 must be taken into consideration. In the ox and pig, tuber- 

 culosis is the commonest cause of compression of the cord, m 

 the sheep coenurosis, in the dog disease of the vertebral joints. 

 Tuberculosis of the internal organs strongly suggests the pos- 

 sibility that this is the cause of the trouble, the presence ot 

 gid in a flock suggests the parasitic nature of the condition, 

 the presence of neoplasms in other parts of the body, and 

 especially in the neighborhood of the vertebral column is more 

 suggestive of a growth in the canal being the cause ot a re- 

 duction in its lumen. If the symptoms of compression set m 

 during the course of a suppurative disease the probability is 

 that the cause is an abscess. 



