Fig. 4.

Measurement of the ejection fraction of the calf pump using strain gauge plethysmography in 18 patients with severe venous insufficiency. The baseline values are reduced (normal values >60%) (left) but show an immediate increase after compression (***p <0.001 compared to baseline) (middle). Repeating the test one week later with stockings (ulcer kit) or inelastic bandages still on the leg (right), EF is still significantly increased under bandages but not under stockings, in spite of the pressure loss being much higher under bandages than under stockings.⁷⁾