Ultrasonic surgical instruments with partially rotating blade and fixed pad arrangement

A method of cutting tissue, comprising:

• inserting a blade of a surgical instrument into a patient wherein the blade is attached to a source of ultrasonic motion and extends through a hollow outer sheath wherein a tissue cutting tip of the blade is exposed through a blade opening in the outer sheath and wherein one of the blade and outer sheath is selectively rotatable relative to the other;
• positioning the blade and outer sheath such that the blade opening is adjacent to target tissue within the patient;
• applying suction through the outer sheath to draw target tissue into the blade opening;
• and
• an oscillating one of the blade and outer sheath relative to the other such that the tissue cutting tip of the blade contacts and traps a portion of the target tissue drawn into the blade opening between the cutting tip and a cutting surface on the outer sheath.

An ultrasonic surgical instrument, comprising:

• a housing;
• an outer sheath supported by said housing and protruding therefrom, said outer sheath having a distal blade opening therein that defines at least one cutting surface;
• an ultrasonic transducer assembly rotatably supported by said housing;
• a blade coupled to said ultrasonic transducer assembly and extending through said outer sheath such that a distal tip of said blade extends into said blade opening wherein a tissue cutting portion thereof protrudes radially out of said blade opening;
• a motor supported by said housing and coupled to said ultrasonic transducer assembly for applying rotational motion thereto such that said tissue cutting portion of said blade is brought into contact with said at least one cutting surface;
• and
• means for limiting an amount of torsion experienced by said tissue cutting portion of said blade when in contact with said cutting surface.