Occurrence.--Shoulder atrophy such as the general practitioner commonly meets with, is an affection, more often seen in young animals and it seems to be due to injuries of various kinds which contuse the muscles of the shoulder. Ill-fitting collars and pulling in a manner that there occurs side draft with unusual strain on the muscles of one side of the neck and shoulder, seem to be the more frequent causes of this trouble. Blows such as are occasioned by kicks and falls frequently result in atrophy of shoulder muscles. Course.--In some cases a rapidly progressive atrophy characterizes the case and lameness and atrophy appear at about the same time. The affection in such instances does not recover spontaneously but constitutes a condition which requires prompt and rational treatment so that function may be fully restored to the parts involved. Occasionally one may observe cases where there is but slight atrophy; where the disease progresses slowly and atrophy is not extensive or marked. In vigorous young animals that are left to run at pasture when so mildly affected, spontaneous recovery occurs. Symptomatology.--Lameness is the first manifestation of shoulder atrophy, and in many cases where lameness is slight, the veterinarian may fail to discover the exact nature of the trouble if he is not very proficient as a diagnostician of lameness or if he is careless in taking into consideration obtainable history, age of the subject, etc. Because of the fact that the average layman believes that practically every case of fore-leg lameness wherein it is not obvious that the cause is elsewhere, is due to a shoulder affection of some kind, we may be too hasty in giving the client assurance that no "sweeny" exists. In some of these cases where a diagnosis of "shoulder lameness" has been made and the client has been assured that no sweeny exists, the patient is returned in about a week and there is then marked atrophy of one or both of the spinatus muscles. A mixed type of lameness characterizes this affection, and in the average case there exists little evidence of local pain. The salient points in recognizing the condition are a consideration of history if obtainable; age of the subject; finding slight local soreness, by carefully manipulating the muscles which are usually involved; noting the character of the lameness if any is present; and where atrophy is evident, of course, the true condition is obvious. Treatment.--Subcutaneous injections of equal parts of refined oil of turpentine and alcohol, with a suitable hypodermic syringe, is a practical and ordinarily effective treatment. From five to fifteen cubic centimeters (the quantity varies with the size of the animal), of this mixture is injected into the atrophied parts at different points, taking care to introduce only about one to two cubic centimeters at each point of injection. The syringe should be sterile and, needless to say, the site of injections must be surgically clean.