A flexible expandable inter vivos tube includes at least one arched segmented portion, a corresponding movable element and at least one positioning mechanism. The at least one arched segmented portion and corresponding movable element forming a flexible closed longitudinally expandable tube. The at least one arched segment includes an H-shaped connector having at least one cavity that allows variable slidable movement of a free end portion of the corresponding movable element. A flexible membrane is contained in the at least one cavity so that the hydraulic or air pressure within an inner rib of the H-shaped connector expands the movable element and, thus, the circumference of the flexible inter vivos tube are increased. The flexible membrane attached to the free end portion limits the travel of the movable element within a corresponding one of the at least one cavity.
