Specialty Exam Results

Clinical Pathology: PCV 32 is not significantly low.  Normal in cattle is 35.    
All hematology parameters are within normal limits and CBC was normal.  This leads us to believe that there is no systemic infection present and the animal is relatively healthy with the exception of the forelimb abnormality.  

Urinalysis: Specific gravity indicates a slight hypersthenuria, which indicates normally functioning kidneys.  There was no increase in the cell numbers in the sediment, indicating normal urinary tract.  

Culture of fracture site:  A mixed culture of E. coli and Staphylococcus aureus indicates infection at the fracture site.  S. aureus is commonly found on the skin of humans and E. coli is commonly found in the gastrointestinal tract and fecal material.  Either of these bacterial species is relatively common and could have contaminated the wound at any time.  

Radiographic interpretation: Distal diaphyseal fracture present on radiographs.  On the dorsopalmar view, it appears as though there are multiple fissure lines but no extra pieces of bone in between.  On the lateral view, the fracture line is oblique from craniodorsal to caudoventral.  There is a significant gap without callous formation between the ends of the fractured bone, which is obvious on the lateral view.  This leads us to call this a delayed union.  From the history we were told that this fracture was not initially stabilized or reduced and the animal was allowed to walk around on the limb.  In addition to infection, these factors could lead to delayed union as will be discussed in the diagnosis. There is no radiographic evidence of sequestra at this time.

On both views, evidence of sclerosis (marked radiopacity) is present on the proximal side of the fracture site and continues up most of the length of the diaphysis.  This evidence is compatible with osteomyelitis as was indicated by the culture.  There was also periosteal proliferation at the margins of the proximal side of the fracture.  This also indicates the presence of inflammation in the bone.  There is also sclerosis and periosteal proliferation on the distal side of the fracture site, but it does not extend as far and does not appear to be as severe.  This may be better for prognosis because it does not appear that the physis is involved.  Involvement of the physis would possibly disrupt normal growth of the bone after fracture is healed.      

Bone proliferation is present at the ends of the fracture site, indicating ability of the bone to respond.  This would lead us to believe that the reasons for nonunion at this time are secondary to other complications and not from a primary failure of the bone to grow.  It also indicates that if the limb were properly reduced and stabilized, with removal of infection, the bone will be able to respond and heal.