Measuring synovial fluid viscosity with a white blood cell diluting pipette. A simple, rapid,and reproducible method.

A convenient and accurate way to measure the relative viscosity of synovial fluid is to use a white blood cell diluting pipette as a simple viscometer. The technique is reproducible with 2% accuracy and adds little to the time required for routine synovial fluid analysis. The magnitude of the variation of synovial fluid viscosity with temperature is demonstrated, and it is suggested that routine clinical measurements be made at room temperature. Clinical data confirm that a single viscosity measurement has little or no diagnostic value.