Endoscopic surgical instruments having rotatable end effectors

Abstract

Medical instruments are provided having end effectors and end effector actuator apparatus which are rotatable relative to the end effectors. The instruments generally include a tube which is typically coupled to the end effectors via a clevis around which the end effectors pivot, a push rod extending through the tube and coupled to the end effectors, an actuator apparatus engaging the tube and the push rod and imparting reciprocal axial motion to the push rod relative to the tube, and end effectors. The actuator apparatus includes a sleeve, spring, handle, and lever arm. The sleeve is movable along the longitudinal axis of the tube against a biasing force of the spring, but is restrained from rotating about the tube. The sleeve has a locking element on its proximal end. The handle surrounds and rotatably engages the proximal end of the tube and has a locking element on its distal end which mates with the locking element of the sleeve and disengages therewith when the sleeve is advanced along the tube. Upon disengagement, the tube, push rod, and end effectors can be rotated. The lever arm pivotally engages the handle and is coupled to the push rod such that pivotal movement of the lever arm relative to the handle effects movement of the push rod relative to the tube and pivotal movement of the end effectors. To decouple rotation of the push rod from the lever arm, a generally spherical push rod engaging element is provided in a generally cylindrical bore of the lever arm.