In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that has an ultrasonic blade that protrudes from at least one ultrasonic transducer that is movably supported within a handle housing. The ultrasonic blade protrudes through an outer sheath assembly that is attached to the handle housing. A distal end portion of the outer sheath has at least one comb-like portion formed thereon. In some embodiments, a distal end of the ultrasonic blade is axially movable adjacent to the at least one comb-like portion. In other embodiments, the distal end of the ultrasonic blade is rotatable adjacent to the at least one comb- like portion.
