The development in the embryo of the lower limbs arteries is made by means of the retrogression of the ischiatic artery, which is initially preponderant, and of the persistence in the popliteal pit of an anastomosis between the original ischiatic axis and the final femoral axis. The tibial arteries originate from one or the other of these axes. The attention is turned to the areas rendered fragile by the complexity of their forming and likely to provoke some topographic anomaly or some dystrophic disease: persistence of the ischiatic artery, trapped popliteal artery, gelatinous dystrophy, Leriche-Fontaine aneurysmal dystrophy, anterior tibial hypoplasia. The repetition of such problems which are non-existent at the upper limbs and are localized to the same arterial segments, especially to the popliteal artery, puts stress upon an eventual dysplasic pathogenesis originating from the embryo.