Role of venous elasticity in the development of varicose veins.

A reduction in the 'elasticity' of the venous system has been proposed as a precursor of venous insufficiency, but the concept remains controversial. This study was designed to develop a method of assessing venous elasticity, and to use this method to investigate the aetiology of varicose veins. Simultaneous measurements of calf volume (determined using strain gauge plethysmography) and venous pressure (obtained via a dorsal foot vein) were made during venous occlusion plethysmography. The elastic modulus, K, defined as stress/strain when the veins are full, was calculated from the pressure/volume relationship. The elastic modulus was determined in 19 normal legs, 33 legs with superficial venous insufficiency, 16 legs with deep venous insufficiency, and 18 legs of a high risk group of volunteers or patients without varicose veins but with a strong history of factors associated with their development. The results showed a clear difference in elasticity between normal limbs and limbs with varicose veins, and also between normal limbs and high risk limbs. These results support the hypothesis that reduced elasticity has a role in the development of varicose veins and precedes the onset of valvular incompetence.