An apparatus includes an elongate member having proximal and distal portions； a rotatable drive cable disposed within the elongate member, the drive cable being connectable to a mechanism to which torque can be applied； and a control assembly mechanically coupled to the drive cable, and configured to disengage the mechanism from the drive cable when the applied torque exceeds a predetermined level, wherein disengagement of the mechanism from the drive cable causes rotation of the drive cable to stop or withdrawal of the drive cable.
