374 



OrCX4}FlSDIA OF LITE STOCK AND OOMFL^TTB STOCK DOOTOB. 



VI. Broken Back. 



Causes. — The back is sometimes broken by heavy objects falling on 

 it ; this quite frequently happens in Northern cities by snow and ice slid- 

 ing off the roofs of houses. Sometimes the horse falls through traps and 

 holes, and the back is sometimes broken when being cast for opera- 

 tions. 



How to know it. — If the spinous processes only are broken, there will 

 not be much change in outward appearance ; but the crepitation charac- 

 teristic of all fractures will be noticed and probably some alteration in 

 the straight outline of the back will follow — it will become depressed in 

 the region of the fracture. But, if the back is broken so as to press 



HORSE SUFFEKING PROM PARTIAL PARALYSIS OF HIND LEGS. 



upon the spinal cord, it will cut oif all sensation and power of motion 

 from all parts back of the fracture. This inability to move and feel is 

 paralysis and is due to the pressure of the broken bones upon the spinal 

 cord. 



Sprain of the psooe muscles is sometimes mistaken for broken back, 

 but the distinguishing difference is very plain, and the test easily applied. 

 Prick the tail or any part back of the fracture with a pin ; if there is no 

 sensation the back is injured, and the spinal cord is enduring pressure ; 

 but if thej9Soce muscles are only sprained, while there will be inability to 

 move the hind legs, there will be sensation and ability to move the tail 

 ivhen pncked with a pin. 



