96 The Diseases of Animals 
under surface of the navicular bone and the tendon that 
passes over it. It occurs in the front feet, and when 
well established is practically incurable. It is usually 
found in horses that are good drivers, and is one of the 
serious diseases to which fast horses are liable. It is 
rarely seen in draft horses. 
The disease comes on gradually without apparent 
cause. The horse points the affected foot out while 
standing. There is little, if any, noticeable inflammation 
in the foot. In moving, the horse does not bend the 
coffin -joint as much as usual, and as a result digs the - 
toe into the ground, and in placing the foot down strikes 
the dirt up forward. There is a decided lameness that 
does not disappear to any extent by driving, and may 
get worse. The horse prefers to stand on the toes as 
much as possible, and as a result the heels are likely to 
be unusually deep. The disease may be easily diagnosed 
by injecting cocaine over the nerves. 
In the early stages, remove the shoes and poultice the 
foot, giving plenty of rest. When the trouble is well 
established there is no eure; the only treatment is a 
surgical operation commonly called “nerving” and 
technically known as neurectomy, or neurotomy. The 
operation consists in cutting ont a section of the nerve. 
that supplies the diseased part. This destroys all 
sensation, but it does not eure the disease. 
There are two methods of operating —the “high,” 
when sections of the nerve are removed on both sides 
of the leg above the fetlock, and the “low,” when sec- 
tions of a nerve are removed on either side in the hollow 
below the fetlock. In the high operation all sensation 
