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SPASM OF THE DIAPHRAGM — THUMPS. 



Spasmodic contraction of the diaphragm, the principal muscle used 

 in respiration, is generally occasioned by extreme and prolonged speed- 

 ing on the ra<je-tracl£ or road. The severe strain thus put upon this 

 muscle finally induces irritation of the nerves coutrolliug it, and the con- 

 tractions become very forcible and violent, giving the jerking charac- 

 ter known among horsemen as thumps. This condition may be distin- 

 guished from violent beating of the heart by feeling the pulse beat at 

 the angle of the jaw, and at the saiuetime watching the jerking move- 

 ment of the body, when it will be discovered that the two bear uo rela- 

 tion to each other. (See "Palpitation of the Heart.") 



SPASM OF THE THIGH, OR CRAMP OF A HIND LIMB. 



This is frequently witnessed in horses that stand on sloping plank 

 floors — generally in cold weather — or it may come on soon after severe 

 exercise. It is probably due to an irritation of the nerves of the thigh. 

 In cramps of the hind leg the limb becomes perfectly rigid, and at- 

 tempts to flex the leg are unsuccessful ; the animal stands on the affected 

 limb, but is unable to move it; it is unnaturally cold; it does uot, how- 

 ever, appear to cause much suffering unless attempts are made to 

 change position. This cramp may beof short duration— a few minutes — 

 or it may persist for several days. This condition is often taken for a dis- 

 location of the stifle-joint. In the latter the foot is extended backward, 

 and the horse is uuable to advance it, but drags the limb after him. An 

 examination of the joint also reveals a change in form. Spasms may 

 affect the eye-lids, by closure or by retraction. Spasm of the steruo- 

 maxillaris muscle has been witnessed, and the animal was unable to 

 close the jaws until the muscle became relaxed. 



Treatment. — An anodyne liniment, composed of chloroform 1 part 

 and soap liniment 4 parts, applied to cramped muscles will usually 

 cause relaxation. This may be used where single external muscles are 

 affected. In spasm of the glottis inhalation of sulphuric ether will 

 give quick relief. In spasm of the diaphragm, rest and the adminis- 

 tration of half an ounce of chloroform in 3 ounces of whisky, with a 

 pint of water added, will generally suffice to bring relief, or if this fails 

 give 5 grains of sulphate of morphia by hypodermic injection. If 

 spasms result from organic disease of the nervous system, the latter 

 sbould receive such treatment as its character demands. In cramp of 

 the leg compulsory movement usually causes relaxation very quickly; 

 therefore, the animal should be led out of the stable and be forced to run 

 or trot. Sudden nervous excitement, caused by a crack of the whip or 

 smart blow, will often bring about immediate relief. Should this fail, 

 the anodyne liniment may be used along the inside of the thigh, and 

 chloroform, ether, or laudanum given internally. An ounce of the 

 chloral hydrate will certainly relieve the spasm when given internally, 



