Devices, systems and methods for delivering a curable, stabilizing material into a central region of a bone structure. Precise placement of the curable substance into a central region of a bone structure through a unipedicular approach. One primary advantage is its ability to create a central cavity in a vertebral body (or to centrally deliver bone cement) through a unipedicular approach. A curved needle having increased rigidity in its flexible end when the end is disposed in its straight position. This increased rigidity is due to a novel tensioning mechanism and to a segmented tube design (as opposed to the conventional longitudinally-slotted tube design).