Interpretation of Specialty Exams

The clinical pathology results showed a slight hypoalbuminemia which resulted in a hypocalcemia.  The calcium level adjusted for albumin is 10.7 mg/dl which is within the normal limits.  The adjusted calcium equation is [calcium level + (3.5 - albumin level) = adjusted calcium].  All other values were normal other than an elevated white blood cell count that is not specific as to cell type.  We can assume that monocytes and neutrophils are elevated as they are the predominant cell type in the joint fluid analysis.  The joint fluid analysis also demonstrated a reddish colored clear fluid which is possibly due to vascular leakage.  The reddish colored joint fluid could have also been caused by a contaminated joint tap.
	The AP view shows an increased joint space on the lateral side and a decreased joint space on the medial side of the stifle joint.  The decreased joint space medially can be due to meniscal tears, however, radiographs are not diagnostic and the phyiscal exam did not produce the "clicking or popping" noise characteristic of meniscal tears.  None the less, we will not rule out meniscal tears until we do an intra-operative exam because 70 - 80% of cranial cruciate ligament ruptures have an accompanying meniscal tear.  The narrowing of the joint space is also a characteristic finding of degenerate joint disease (DJD).  The abnormal joint spaces could also be attributed to poor positioning/uneven stress to the joint.  There is also an apparent flattening of the articular surfaces of the tibia on the AP view.  This finding is also noted in DJD.  Likewise, the lateral view of the stifle showed signs characteristic of DJD.  For instance, there is periarticular osteophyte formation  and subchondral bone sclerosis of the caudal tibial plateau.  Although it is not commonly diagnosed radiographically we do suspect that there is a rupture of the cranial cruciate ligament based on the ostoearthritic changes noted on the radiographs.  The use of skyline, and/or oblique views, as well as some views of the contralateral limb, would be best for diagnosing further osteoarthritic changes.