A surgical instrument includes a housing, and a shaft including a proximal end, a deflectable portion and a distal tip. A handle is movable between first and second positions on the housing, and an actuator is movably coupled to the handle, such that movement of the handle between its first and second positions causes a corresponding movement of the actuator between first and second positions in the housing. A deflection wire includes proximal and distal portions, the distal portion being fixed to the shaft, and the proximal portion being affixed to the housing so as to provide a path length for the deflection wire within the housing. The movement of the handle causes the actuator to move to its second position, the second position of the actuator causing an increase in the path length for the deflection wire so as cause a deflection of the distal tip of the shaft.