366 ARTICULAR RHEUMATISM— POLYARTHRITIS 



diseases of serous membranes will bring on attacks of muscu- 

 lar rheumatism in a similar manner as articular rheumatism. 

 (d) Injuries to the muscles, overexertion without previous 

 exercise, will produce similar symptoms. This, however, 

 should not be classed as muscular rheumatism. 



Pathology.— On examination the muscles will show serous 

 inflammation with infiltration of the intramuscular con- 

 nective tissue. Disintegration and fatty degeneration are 

 found in most cases. The muscular tissue shows evidence 

 of hyperemia and swelling. In chronic cases the fibrous 

 connective tissue elements are thickened. 



Symptoms.— Pain is always a prominent symptom. This 

 may be constant in severe attacks or in the milder forms 

 periodic and recurrent. In dogs the condition very often 

 comes on suddenly without any prodromal symptoms. The 

 attack is usually transient lasting from a few hours to several 

 weeks, and is very apt to recur. The symptoms of muscular 

 rheumatism will depend somewhat upon the groups of muscles 

 affected. Sometimes the muscles of the head and neck are 

 involved; in this case the head and neck will be more or less 

 fixed, the animal holding the head in a rigid position. When 

 manipulated or the animal made to move indications of severe 

 pain are noted. In other cases the muscles over the scapula 

 will show the primary seat of the disease. This is often 

 unilateral, but may be present on both sides. The anterior 

 limb will be relaxed or the animal show marked lameness 

 when weight is placed on it. When bilateral the animal 

 may be found in a recumbent position, with the limbs 

 straightened out, and refuses to get up. The patient cries 

 out and whines when the muscles are palpated. 



In involvement of the muscles of the back (lumbago 

 rheumatica) the animal assumes a rigid attitude, very 

 cautious in all its movements, frequently refusing to move 

 and when forced to do so great pain is manifest. Occasionally 

 the patient will be found lying down. Manipulation of the 

 muscles over the region produces intense pain. When the 

 muscles of the extremities are primarily affected the animal 

 lies on its back with the feet upward, whining and crying. 

 Feces and urine are often retained when the abdominal 



