Hypothesis 3:  Infection/ Inflammation

	TitanŐs physical findings may be related to an infection that has lead to an 
inflammatory response in the joint.  This theory is supported by a previous trauma.  He 
fell off the bed, and also he plays regularly with the other household dog.  Playing may 
have lead to a penetrating bit or scratch wound that allowed for the introduction of 
bacteria.  The previous trauma may have predisposed him to develop septic arthritis in 
one or more of his synovial joints.  Another predisposing factor is the fact that Titan has 
allergies.  Allergies often lead to skin infections which may result in the introduction of 
bacteria to the bloodstream.  
	
	Common aerobic bacteria include staphlococcus, streptococcus, coliforms, and 
pasterella.  Common anaerobic bacteria include fusobacterium, bacteroides, and 
peptostreptococcus.  Fungi may also be a source of infection in to a wound.  

	Titan is also experiencing a Grade III/VI non-weight bearing lameness.  This is a 
common historical finding with infected joints.  Bacterial infection often causes pain, 
swelling, and inflammation in the joints; commonly the stifle joint.