208 LAMENESS OF THE HORSE 



siieh instances constitutes a source of some trouble, but the aver- 

 age mare offers no serious resistance to the confinement occa- 

 sioned by the sling. 



Good hygienic care, a suitalile diet and full i^hysiological doses 

 of strychnin are indicated. Cadiot and Almy recommend vaginal 

 douches of cold water and counterirritation of the region of the 

 inner thigh in these cases. 



Paralysis of the Sciatic Nerve. 



Anatomy. — The great sciatic nerve leaves the pelvis in com- 

 pany with the gluteal nerves, through the great sciatic foramen 

 (notch), passing downward along the posterior face of the femur. 

 Near the stifle it passes between the two heads of the gastroc- 

 nemius muscle and continues as the tibial. Branches supply 

 the following muscles — ol)turat<)r, semimem])ranosus (adductor 

 magnus), biceps femoris (triceps abductor femoris), semitendi- 

 nosus (biceps rotator tibialis), lateral extensor (peroneus) and 

 the tibial nerve, its continuation, innervates the digital flexors. 



Etiology and Occurrence. — Paralysis of the great sciatic 

 nerve may be caused by central disorders, injury in falling, frac- 

 tures and new growths. Because of its protected position, this 

 nerve does not often suffer injury, and paralysis of the sciatic 

 nerve is recorded in a few instances owing to its rarity. 



Symptomatology. — When consideration is given the number 

 of muscles that are supplied by the sciatic nerve and the func- 

 tion of these muscular structures, it is obvious that the leg 

 cannot be used in sciatic paralysis. However, the limb is 

 capable of sustaining weight when it is fixed in position, but this 

 is done without exertion of muscular fibers which are supplied 

 by the great sciatic nerve. Trotting is impossilile and flexion 

 of the affected member is also likewise precluded. The foot is 

 dragged when the subject is caused to advance. 



Under the heading "sciatica," Scott^ has described a case of 

 acute sciatic affection wherein a pacing horse manifested evidence 

 of great pain of a nervous character. There were muscular 



iDr. John .Scott, Peoria, III., in The American Veterinary Review, Vol. 16, 

 page 16. 



