The present study has revealed the relationship between the cross sectional area of the great saphenous vein and the degree of tension in the superficial fascia of the thigh. We conducted an ultrasound examination with 27 patients (54 lower limbs) in both standing and walking positions. With an increase and decrease in the degree of tension of the superficial fascia, the blood is pushed to the sapheno-femoral junction. Nearly 200 mm3 of blood flows in, and is pushed out of, a 100-mm great saphenous vein segment in the thigh, towards the sapheno-femoral junction during a step cycle. As a result, the active function of the fascial compartment of the great saphenous vein has been found. We have called this mechanism the superficial venous pump.
Superficial venous pump; great saphenous vein; venous outflow.