1. A device for aiding the selection of a restraint orthosis of compressive orthosis type made of elastic or inelastic material, and its adaptation to the morphology of a limb for which this orthosis is intended, this device comprising: means ( 10 ) for numerically simulating the action of the restraint on the hemodynamics of the venous return, able to deliver values of blood flow rate and/or intravenous pressure at a plurality of points of a numerical model representative of the sural venous network of a limb, and means ( 26 ) for presenting said values of blood flow rate and/or intravenous pressure determined by these numerical simulation means, which device is characterized in that it furthermore comprises means ( 14 ; 16 ) for: producing restraint pressure values capable of being exerted by said orthosis at the surface of the limb at a corresponding plurality of predetermined points, and applying the values thus produced as input to said numerical simulation means ( 10 ).