A method of making a contoured internal limb including providing a flattened tubular segment of graft material, and a prosthesis including the contoured internal limb. The tubular segment includes a left lateral edge, a right lateral edge, a first length extending from the left lateral edge to the right lateral edge, and a second length extending from a proximal end to a distal end of the tubular segment. The method also includes contouring a proximal portion, a middle portion, and a distal portion of the contoured internal limb from the tubular segment. The method also includes closing a right lateral edge of the proximal portion and a right lateral edge of a first section of the middle portion. The method further includes removing the proximal, middle and distal portions of the contoured internal limb from the tubular segment and maintaining a second section of the middle portion as circumferentially continuous.