The venous system of the lower limbs.

The venous system anatomy of the lower limbs and especially its functionality still presents half-lighted areas, fact easily qualified as incredible for the third millennium. Our dissections on fresh amputation segments, methylene blue injected in superficial veins or in deeper veins pointed out that venous circulation is much more complex than it seemed, that there are subdermal collectors connected to the saphene trunks which permit bidirectional transfer of blood mass to saphene venous roots or to derm. The dermal plexus has also a complex connection with the deep venous system by Delater perforators, by perforators, which drain saphene systems after having previously received dermal affluents, and by Delater equivalences (submillimetric perforators) that provide blood mass transfer from deep to surface under the conditions of a moderate and temporary venous hypertension. High- and long-term venous hypertension determines the valvular device deterioration of classical perforators making possible a pathological bi-directional flow.