[Structural features, biomechanical properties of the cusps of venous valves and walls of lower extremity veins in humans].

Relative tensility and resistivity of walls of superficial and deep veins were studied on 200 lower extremities in persona at the age of 4--86 years. The ability of valves to resist the retrograde liquor flow was studied on the same veins. The data on the valves "endurance" were compared with the character of their connective tissue framework. Relative lengthening of the venous walls increases up to 30--35 years of age, after that time these indices decrease. The wall resistivity is higher in the deep than in the superficial veins. The ability of the lower extremity valves to resist the retrograde liquor pressure is gradually increasing up to 60 years of age, and afterwards this ability is somewhat decreasing.