Collateral circulation in distal occlusion of lower limb arteries: an anatomical study and statistical research in 40 elderly subjects by echo-color-Doppler method.

The collateral circles and their hemodynamic significance in distal lower limb arterial occlusion have been described in an elderly population. Overall 40 subjects (20 men and 20 women; age range 66-83) with symptomatic lower limb arteriopathy (Fontaine's stage II) have been studied combing Contrast Angiography and Color Doppler Echography of the lower limb arterial district. In our population, the results showed that the tibialis arteries were the vessels most often involved in arterial occlusion (posterior tibialis a., 15 cases = 37.5%, posterior tibialis a., 12 cases = 30%), followed by the peroneal a. (8 cases = 20%) and by the popliteal a. (5 cases, 12.5%). In the occlusion of the popliteal artery the collateral circle was mainly established through the deep femoral a., the great anastomotic a., the recurrent posterior tibialis a., and from the articular supero-lateral a. In the occlusion of the anterior tibialis artery the collateral circulation was ensured through the collateral posterior tibialis as. and through the collateral perineal as. In the occlusion of the posterior tibialis a., the collateral circle was established through the great anastomotic a., through the branchers of the arterial circle of the ankle and from the perforating plantar as. (anterior tibial a.). Finally, in the occlusion of the peroneal a., the collateral circulation was only represented by branches of the arterial circle of the ankle. The hemodynamic compromission, measured by the Windsor Index, was the highest for popliteal occlusions (mean IW = 34.3%). Occlusions of the anterior tibialis a. (mean IW. = 35.48%), of the peroneal a. (mean IW = 44.71%), and of the posterior tibialis a. (mean IW = 55.44%) showed progressively lower hemodynamic compromission. Gender differences in hemodynamic significance at each level of occlusion were not significant.