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aro peculiar to themselves, and yet the trouble is frequently mistaken 

 for other affections— navicular disease more often than any other. The 

 fact that in both affections there are instances when the external symp- 

 toms are but imperfectly defined, and that one of them especially is 

 very similar in both, is sufficient to mislead careless or inexperienced 

 observers and to occasion the error which is sometimes committed of 

 applying to one disease the name of the other, erring both ways in the 

 interchange. The true designation of pathological lesions is very far, 

 at times, from being of certain and easy accomplishment, and owing 

 to the massive structure of the parts we are considering this is espe- 

 cially true in the present connection. And still there are many cases 

 in which there is really no reasonable excuse for an error in diagnosis 

 by an average practitioner. 



Shoulder lameness will of course manifest itself by signs and appear- 

 ances more or less distinct and pronounced, according to the nature of 

 the degree and the extent of the originating cause. We summarize 

 some of these signs and appearances : 



The lameness is not intermittent but continued, the disturbance of 

 motion gauging the severity of the lesion and its extent. It is more 

 marked when the bones are diseased than when the muscles alone are 

 affected. When in motion the two upper bony levers, the shoulder 

 blade and the bone of the upper arm, are reduced to nearly complete 

 immobility and the walking is performed by the complete displacement 

 of the entire mass, which is dragged forward without either flexion or 

 extension. The action of the joint below, as a natural consequence, is 

 limited in its flexion. In many instances there is a certain amount of 

 swelling at the point of injury— at the joint, or more commonly in front 

 of it, or on the surface of the spinatus muscle. Again, instead of swell- 

 ing there will be muscular atrophy, though while this condition of loss 

 of muscular power may interfere with perfect locomotion, it is not in 

 itself usually a cause of shoulder lameness. " Swenied " shoulders are 

 more often due to disease below the fetlock than to affections above the 

 elbow. 



During rest the animal often carries his leg forward, somewhat anal- 

 ogous to the "pointing" position of navicular disease, though in some 

 cases the painful member drops at the elbow in a semi-flexed position. 

 The backing is sometimes typical, the animal when performing it, in- 

 stead of flexing his shoulder, dragging the whole leg without motion in 

 the upper segment of the extremity. The peculiar manner in which 

 the leg is carried forward in the act of walking or trotting is in some 

 instances characteristic of injuries of the shoulder, the power of exten- 

 sion being limited 5 the whole leg in the act of locomotion is moved for- 

 ward with a circumflex, swinging motion, which distinguishes this pecu- 

 liar affection from others. 



With the utmost scrutiny and care the vagueness and uncertainty of 

 the symptoms will contribute to perplex and discredit the diagnosis 



