Group 15   Case 4
Perhaps the initial impact of the car was on the dog's right side, which caused a secondary 
Impact on the right side - possibly in the hip area.  


Hypothesis 2: Fracture of the right tibia with fracture of the left side of the pelvis with possible abdominal inujury (ruptured bladder, spleen etc.) or thoracic injury (traumatic myocarditis, pneumothorax, or fractured rib)
Both legs have pain sensation and are capable of movement, but incapable of weight bearing.  Reflexes are questionable.  This is a bilateral class 4 lameness.  Right Tibia presents with abrasions of the lateral side and swelling distal to the stifle.   The joints seem normal, but the continuity of the tibia is questionable because of palpable instability. 

The entire left limb is swollen with abnormal movement proximal to the stifle and crepitations.  Physical exam in unable to localize injury.  All joints distal to the hip appear normal.  A fracture of the left os coxae would lead to crepitations due to abnormal contact with femoral head, loose pieces of bone, or soft tissue swelling.  


Swelling in both limbs is possibly due to damage tof soft tissue and vessles which caused 
hematoma formation and increased fluid leakage from vasculature.  Consequent necrosis of 
tissue and infiltration of inflammatory cells and mediators will contribute to pain and 
swelling.  

As with any HBC, injury to spleen, bladder, liver, ribs, myocardium, etc should be investigated.