A surgical instrument having a handle assembly and an elongated shaft assembly protruding therefrom. Various embodiments of the elongated shaft assemblies include reconfigurable shaft segments that have portions that may be selectively arranged in coaxial alignment with each other and in other configurations wherein at least some portions thereof are not in coaxial alignment with each other. Various locking arrangements are disclosed for releasably locking the reconfigurable shaft segments in desired orientations. A movable closure tube is supported on the elongated shaft segment and is oriented to provide actuation motions to an end effector coupled to the distal end of the elongated shaft.