Introduction

Osteoarthritis (OA) can be considered as a primary or secondary cause of cranial cruciate ligament rupture (CCLR) in canines. While research has so far been focused on OA biomarkers that can provide information about joint changes prior to the development of late stage of degenerative processes, none of this is currently in use in clinical practice.

Objectives

The aim of our study was to evaluate changes in canine synovial fluid physical properties, cells quantity and composition from synovial fluid smear.

Methods

The concentration of biomarkers CRP and COMP in plasma and synovial fluid were evaluated using ELISA kits. Samples of synovial fluid was taken from two groups of Labrador retrievers. While the first group consisted of patients in which the cranial cruciate ligament rupture has been diagnosed (n=30), the second (control) group was composed of clinically healthy patients (n=10).

Results

In control group, the samples of synovial fluid were of yellow-grey color, medium viscosity, not turbid and tested positive for the mucin clot test. The majority of the canine synovial fluid samples from the first group displayed a yellow-grey color, was non-viscous while the mucin clot test was negative and without turbidity. In the same group we observed an increase of neutrophil and mononuclear cells, as well as of biomarkers CRP and COMP from plasma and synovial fluid.

Conclusions

It was shown that synovial fluid analysis is a particularly important diagnostic tool, especially when there is no clinical evidence of OA, and could be valuable for detection of early degenerative changes in the cartilage.