Transfemoral Socket Design and Muscle Function

"The sub-ischial socket includes a firm, compressive, preferably cylindrical, fabric-covered silicone liner, a flexible inner socket, and a shorter rigid outer socket. The socket has proximal trim lines that do not impinge on the pelvis; they terminate distal to the ischial tuberosity and greater trochanter. For the NU-FlexSIS Socket, passive suction suspension is achieved using a one way valve and a liner with an internal seal.~Since the prosthetic socket is a custom-made device, it is considered Class I exempt by the Food and Drug Administration (FDA)."