Group 15
Diagnosis:
 

   The radiographs show a complete simple fracture of the articular 
surface of the olecranon.  The fracture does not seem to involve the 
proximal radial growth plate.  This most closely resembles our 
hypothesis 2 (traumatic fracture of the olecranon or proximal ulna 
of the right front limb).
   When the foal was kicked, the impact caused this complete 
fracture without obvious trauma to the skin. During the physical 
exam, no instability or crepitance was noted.  This was probably due 
to the nature of the physical exam;  more pressure could have 
elicited crepitance or instability in the region of the elbow.  The 
swelling probably has a masking effect. Contrary to our hypothesis, 
the fracture is complete.  However, the foal does bear weight.  The 
radius bears the foals weight while standing.  The stoic nature of 
the foal allows it to bear weight without showing pain.    
  As the foal has kept his shoulder and upper arm in a stationary, 
relaxed position for 2 weeks, the muscle fibers of the triceps have 
begun to shrink due to lack of use (atrophy).  The foal also 
appears to stand with the tip of his hoof resting on the ground.  
This position relieves some of the weight on his leg, but places his 
fetlock and pastern in a flexed position.  Over the two weeks, this 
position has probably stretched the extensor tendons 
while simultaneously allowing the flexor tendons to contract.
    Due to the direct trauma of the kick and the subsequent 
inflammation, blood vessels have leaked into the area (damaged 
vessel walls or increased permeability due to 
inflammatory mediators) causing edema.  The local release of 
prostaglandins causes pain.  In the 2 weeks since the injury, the 
inflammation has probably subsided somewhat; the area 
did not present with heat.