An ultrasonic surgical instrument comprises a cylindrical shaft and a blade at a distal or free end of the shaft, the blade being unitary and continuous with the shaft, without an intervening joint. The shaft has a longitudinal axis and the blade includes a flat or planar blade body with a proximal end eccentrically disposed relative to the shaft axis. Thus, the blade body or at least a proximal end portion thereof is disposed eccentrically relative to the shaft. The blade in its entirely may be inclined relative to the shaft axis or extend parallel thereto.