Patent ID: 8043296

Claim:
An apparatus, comprising: an elongated member; an expandable member coupled to the elongated member; an outer sheath disposed about the expandable member such that an outer surface of the expandable member is in discontinuous contact with an inner surface of the outer sheath; and an actuator coupled to the elongated member having a first component and a second component and operable to control twisting of the expandable member about the elongated member, the actuator having a first position in which the first and second components interface with each other to prevent twisting of the expandable member about the elongated member in a first direction and a second position in which the first and second components are separated from each other to allow twisting of the expandable member about the elongated member in the first direction, the expandable member and the outer sheath configured to cooperatively displace a bone structure when moving between a collapsed configuration and an expanded configuration.