[Intra- and extra-pelvic venous connections. Anatomical study]

Regarding to clinical diseases, the authors emphasize the important part of pelvic veins as collateral flows when iliac channels are occluded. They point out the three mains streams of this collateral network: the obturator veins, the gluteal veins, and the pudendal veins. Longitudinal anastomoses are connected each other by transversal veins such as Santorini plexus, and sacral veins; they allow venous supply from one side to the other when two levels or more are involved.