ELEMENTS OF HIPPOLOGY. 



135 



surface becomes rough and chafes the sheath of the tendon, 

 and, as the bone is inaccessible to the surgeon, the evil done is 

 irremedial. Navicular disease is incurable and very painful. 

 In order to render the horse unconscious of this pain, and so 



prolong i t s usefulness 

 until a complete break- 

 down occurs, a portion 

 of the sensory nerve sup- 

 plying the foot is re- 

 moved by an operation 

 called neurotomy. 



"In the early stages of 

 navicular disease the 

 symptoms are generally 

 very obscure. When the 

 disease begins in inflam- 

 mation of the navicular 

 bone, the animal, while 

 at rest, 'points' the af- 

 fected foot a time before 

 any. lameness is seen. 

 While at work, he ap- 

 parently travels as well 

 as ever, but when placed 

 in the stable, one foot is 

 set out in front of the 

 other, resting on the toe, 

 with fetlock and knee 

 flexed. After a time, 

 if the case is closely 

 watched, the animal takes a few lame steps while at work, 

 but the lameness disappears as suddenly as it came, and 

 the driver doubts if the animal was really lame at all. Later 

 on the patient has a lame spell, which may last during the greater 



Figure 88. 



