A pilot study comparing the use of below-knee and above-knee graduated stockings in patients with superficial venous incompetence

Objective: Investigation of the effects of high- and low-ankle-pressure, ab ove- and below-knee compression stockings on the haemodynamics of normal an d superficially incompetent venous systems. Design: Prospective duplex study of a normal group and a venous incompetenc e group randomised to high- or low-pressure stockings. Setting: Vascular services of a University Hospital. Subjects: Six subjects with normal venous haemodynamics (12 limbs) and 12 p atients with venous incompetence (20 limbs). Methods: Subjects wore below-knee and then above-knee stockings for 1 week each. Duplex scans were performed at the outset and end of the study and on fitting and after wearing each stocking type. Main outcome measures: Duplex-derived femoral and popliteal venous velociti es were measured and indexed against the initial velocity. Results: Below-knee stockings produced only minor changes. Above-knee stock ings produced increased velocities in normal subjects. Similar changes were only seen with higher-pressure stockings in patients with incompetence. Conclusion: Above-knee, high-ankle-pressure stockings produce increased dee p venous flow velocities.