SHOULDER-SLIP. 245 



muscles on the inner side contract forcibly, in consequence 

 of which a bulging of the shoulder occurs, giving it the 

 appearance of being out of place ; hence the name shoulder- 

 slip. 



Patliology. — Injury occurring to some part of the limb, in- 

 flammatory action, more or less severe, results, and atrophy 

 of the muscles of the shoulder follows in due course of time, 

 either as the result of some interference with the nutrition 

 of the part — which is usually the case where the injury is 

 in connection with the shoulder — or as a result of func- 

 tional inactivity, as in long-standing cases of navicular 

 arthritis, when atrophy of the scapular muscles may occur in 

 consequence of not receiving a proper amount of exercise. 



Causes. — Shoulder-slip may be caused in a large variety 

 of ways, hence it is a condition rather frequently met with. 

 It may be produced by direct or indirect injury. It is most 

 commonly seen in young horses, when the muscles are soft, 

 and consequently more susceptible to injur}^ than those of 

 a mature horse, and more especially when such horses are 

 from the country. It may result from putting a horse to 

 work too soon. Ploughing is a very prolific cause, where 

 the animal walks with one foot in the furrow and one foot 

 out ; in such a case probably it is due to the irregular action. 

 Sudden jerks, such as might be caused by a plough striking 

 a root, or snag, or suddenly starting a heavy load, a badly- 

 fitting collar, jolts or jars, bruises, concussion, or any injury 

 to the shoulder, etc., all tend to produce the condition known 

 as shoulder-slip ; and, as before stated, it may occur in con- 

 sequence of functional inactivity, this form being seen in 

 connection with chronic lameness and injuries situated be- 

 low the shoulder, as navicular arthritis, carpitis, etc. 



Symptoms. — In some cases the presence of inflammation 

 may be detected before the muscles have wasted ; but, as a 

 rule, atrophy is the first symptom to present itself to the 



