Surgical tool having positively positionable tendon-actuated multi-disk wrist joint

A minimally invasive surgical instrument comprising:

• an elongate shaft having a working end, a proximal end, and a shaft axis between the working end and the proximal end;
• a wrist member having a proximal portion connected to the working end, wherein the wrist member comprises at least three vertebrae connected in series between the working end of the elongate shaft and the end effector, the vertebrae including a proximal vertebra connected to the working end of the elongate shaft and a distal vertebra connected to the end effector, each vertebra being pivotable relative to an adjacent vertebra by a pivotable vertebral joint, at least one of the vertebrae being pivotable relative to an adjacent vertebra by a pitch joint around a pitch axis which is nonparallel to the shaft axis, at least one of the vertebrae being pivotable relative to an adjacent vertebra by a yaw joint around a yaw axis which is nonparallel to the shaft axis and perpendicular to the pitch axis;
• an end effector connected to a distal portion of the wrist member;
• and
• a plurality of cables coupled with the vertebrae to move the vertebrae relative to each other, the plurality of cables including at least one distal cable coupled with the terminating at the distal vertebra and extending proximally to a cable actuator member, and at least one intermediate cable coupled with and terminating at an intermediate vertebra disposed between the proximal vertebra and the distal vertebra and extending to the cable actuator member, the cable actuator member being configured to adjust positions of the vertebrae by moving the distal cable by a distal displacement and the intermediate cable by an intermediate displacement shorter than the distal displacement.

A method of performing minimally invasive endoscopic surgery in a body cavity of a patient, the method comprising:

• introducing an elongate shaft having a working end into the cavity, the elongate shaft having a proximal end and a shaft axis between the working end and the proximal end;
• providing a wrist member which comprises at least three vertebrae connected in series between the working end of the elongate shaft and the end effector, the vertebrae including a proximal vertebra connected to the working end of the elongate shaft and a distal vertebra connected to the end effector, each vertebra being pivotable relative to an adjacent vertebra by a pivotal coupling;
• providing an end effector connected to a distal portion of the wrist member;
• positioning the end effector by rotating the wrist member to pivot at least one vertebra relative to an adjacent vertebra by a pivotal pitch coupling around a pitch axis which is nonparallel to the shaft axis;
• and
• repositioning the end effector by rotating the wrist member to pivot at least one vertebra relative to an adjacent vertebra by another pivotal coupling around a second axis which is nonparallel to the shaft axis and nonparallel to the pitch axis.

A medical instrument comprising:

• a base shaft having a working end, a proximal end, and a shaft axis between the working end and the proximal end;
• a segmented wrist member comprising a plurality of spaced-apart segment vertebrae disposed sequentially adjacent to one another along a wrist longitudinal line, the plurality of vertebrae including:
• a proximal vertebra connected to the shaft working end;
• a distal vertebra supporting an end effector;
• at least one intermediate vertebra disposed between the proximal vertebra and the distal vertebra, the at least one intermediate vertebrae being connected to each adjacent vertebra by a pivotally movable segment coupling, each segment coupling having a coupling axis nonparallel to the wrist longitudinal line, and at least two of the coupling axes being non-parallel to one another, at least one of the intermediate vertebrae being a medial vertebra;
• a plurality of movable tendon elements disposed generally longitudinally with respect to the shaft and wrist member, the tendon elements each having a proximal portion, and having a distal portion connected to one of the distal vertebra and the medial vertebra so as to pivotally actuate the connected vertebra, at least one of the tendons being connected to the at least one medial vertebra and at least one of the tendons being connected to the distal vertebra;
• and
• a tendon actuation mechanism drivingly coupled to the tendons and configured to controllably move at least selected ones of the plurality of tendons so as to pivotally actuate the plurality of connected vertebrae to laterally bend the wrist member with respect to the shaft.

A minimally invasive surgical instrument comprising:

• a shaft having a working end, a proximal end, and a shaft axis between the working end and the proximal end;
• a segmented wrist member comprising a plurality of spaced-apart segment vertebrae disposed sequentially adjacent to one another along a wrist longitudinal line, the plurality of vertebrae including a proximal vertebra connected to the shaft working end, a distal vertebra supporting an end effector, and at least one intermediate vertebra disposed between the proximal vertebra and the distal vertebra;
• the at least one intermediate vertebrae being connected to each adjacent vertebra by a pivotally movable segment coupling, each segment coupling having a coupling axis nonparallel to the wrist longitudinal line, and at least two of the coupling axes being nonparallel to one another;
• the movable segment couplings including at least one spring-like element arranged to regulate the pivotal motion of at least one adjacent vertebra;
• a plurality of movable tendon elements disposed generally longitudinally with respect to the shaft and wrist member, the tendon elements each having a proximal portion, and having a distal portion connected to the distal vertebra so as to pivotally actuate the distal vertebra;
• and
• a tendon actuation mechanism drivingly coupled to the tendons and configured to controllably move at least one of the plurality of tendons so as to pivotally actuate the plurality of connected vertebrae to laterally bend the wrist member with respect to the shaft.