Measuring units for elastic stockings: priority to mmHg rather than classes.

Seven incontrovertible arguments show that the only valid measurement unit for elastic stockings is the millimetre of mercury and not a grading system. The mmHg is an international measurement unit; a new European grading system will make prescribing much more difficult; the degree of arterial insufficiency is calculated by taking systolic pressures by Doppler and is expressed in mmHg; in case of superimposition of elastic stocking, pressure add together but not grades; the unit used for pressure instruments is the mmHg; a clinical situation may require a compression force straddled between two grades; finally, new materials will certainly provide increasingly precise forces.