The present invention relates to anti-displacement prosthetic system, comprising: a liner for fitting over a residual limb; a socket for donning over the liner; and characterized by: a first fastening means located on an inner side of the socket, wherein said first fastening means is removably attachable to an outer surface of the liner; a valve assembly releasably mounted on the socket and coupled to the first fastening means for removing air between the liner and the socket, to prevent displacement of the liner within the socket; wherein the liner and the first fastening means are provided with complementary fastening elements; and wherein the valve assembly comprising a cap having an opening, a second fastening means complementary to the first fastening mean, and a piston for generating a vacuum, coupled to the opening of the cap.