An implantable inflatable penile prosthesis cylinder includes an outer tube member having a longitudinal axis, an inner tube member contained within the outer tube member, and one or more tensile support members within the inner tube member. The inner tube member includes at least one inflatable chamber section, at least a portion of which is defined by a wall of the inner tube member. The one or more tensile support members extend between interior surfaces of the wall, and are placed in tension when the at least one chamber section is in an inflated state.
