LAMENESS IN THE REGION OF THE SHOULDER. 39 



2. — Luxation of the Scapulo-humeral Articulation. 



History. — Sudden severe lameness following falls, slips 

 and jumping. 



Inspection. — Severe swinging-leg lameness, shortening of 

 the leg, with more or less swelling about the articulation. 



Falpation. — Passive movements of the articulation, as 

 flexion and extension, are almost impossible ; adduction and 

 abduction are exceedingly free. Above and in front of the 

 glenoid cavity of the scapula the head of the humerus can 

 be felt, provided inflammatory swelling does not interfere 

 with palpation. Pressure upon this region is painful. This 

 condition is often complicated with fracture of the scapula 

 and humerus. 



3. — Inflammation of the Bursa and Tendon of the 

 Postea-spinatus Muscle. 



Anatomy. — A wide and flattened muscle, having its fixed 

 insertion in the postea spinatus fossa, scapular spine and 

 tuberosity, cartilage of prolongation and internal face of the 

 scapular aponeurosis. It terminates inferiorly by two 

 branches; the external one, the strongest, is inserted in the 

 crest of the external tuberosity of the humerus, first gliding 

 over a synovial bursa situated above its point of inSertion. 

 This muscle is an outward rotator and abductor of the 

 humerus. (Chauveau.) 



History. — Lameness following kicks, falls, collisions and 

 sudden turning while speeding. 



Inspection. — Abduction of the entire leg with supporting- 

 leg lameness. The animal still supports the weight of the 

 body, but while doing so abducts the leg as much as possible. 



Palpation. — Usually increased heat and swelling can be 

 felt over the external trochanter of the humerus. Pressure 



