Value of direct smears of synovial fluid in the diagnosis of canine joint disease.

Assessments of direct smears of synovial fluid by four clinicians were compared with the results obtained with a Coulter counter. Estimates of total white cell counts by the clinicians were inaccurate and generally higher than the Coulter counter results. The method had a low sensitivity and specificity for the identification of degenerative joint disease and normal joints in comparison with the identification of inflammatory joint disease. There were marked variations in the results obtained by the four clinicians for all the analyses in the study.