Laparoscopic devices with flexible actuation mechanisms
View Patent ↗Methods and devices are provided for performing minimally invasive surgical procedures. In one embodiment, a surgical device is provided that includes an elongate shaft having an end effector at a distal end thereof. The end effector can be configured to be movable between a first configuration in which the end effector is longitudinally aligned with or linear relative to the shaft and a second configuration in which the end effector is articulated at an angle beyond 45 degrees relative to the shaft. With the end effector in the first configuration or in the second configuration, the device can be configured to allow selective actuation of the end effector.
1. A laparoscopic device, comprising:
an elongate shaft having proximal and distal ends defining a longitudinal axis extending therebetween, the elongate shaft having an inner lumen extending therethrough between the proximal and distal ends;
an end effector coupled to the distal end of the elongate shaft; and
an actuator element coupled to the end effector and extending between the proximal and distal ends of the elongate shaft along the longitudinal axis through the inner lumen, a proximal portion of the actuator element being rigid and a distal portion of the actuator element being flexible, the distal portion formed of a composite material including a solid core formed of a first material and an outer sheath formed of a second material having a greater flexibility than the first material, the outer sheath surrounding the solid core and being non-slidable relative thereto;
wherein the actuator element is movable relative to the elongate shaft to actuate the end effector, and
wherein the outer sheath includes a plurality of features extending therefrom and disposed in the elongate shaft, the plurality of features changing a stiffness of the actuator element when the actuator element is flexed.
2. The device of claim 1 , wherein the first material comprises a metal and the second material comprises a plastic.
3. The device of claim 1 , wherein the distal portion has a stiffness that is configured to change during the actuation of the end effector.
4. The device of claim 1 , further comprising an articulator element coupled to the end effector and extending through the inner lumen of the elongate shaft between the proximal and distal ends of the elongate shaft, the articulator element being configured to articulate the end effector to angularly orient the end effector relative to the longitudinal axis of the elongate shaft.
5. The device of claim 4 , wherein the articulator element extends through the inner lumen on one side of the inner lumen, and the actuator element extends through the inner lumen on an opposite side of the inner lumen.
6. A laparoscopic device, comprising:
a cannulated elongate shaft having proximal and distal ends defining a longitudinal axis extending therebetween;
an end effector coupled to the distal end of the shaft; and
an actuator element coupled to the end effector and extending through the cannulated elongate shaft, the actuator element including a rigid proximal portion and a flexible distal portion, the actuator element being formed of a composite material including a sheath surrounding a central core;
wherein the actuator element is movable relative to the cannulated elongate shaft to actuate the end effector, and
wherein the sheath has a plurality of features extending therefrom and disposed in the cannulated elongate shaft, the plurality of features changing a stiffness of the actuator element when the actuator element is flexed.
7. The device of claim 6 , wherein the central core is formed of a metal, and the sheath is formed of a plastic.
8. The device of claim 6 , wherein the plurality of features include a plurality of ribs extending radially outward from the central core.
9. The device of claim 8 , wherein the plurality of ribs are configured to compress together to increase the stiffness of the actuator element when the actuator element moves to actuate the end effector.
10. The device of claim 8 , wherein each of the plurality of ribs include a base portion that is substantially perpendicular to a longitudinal axis of the core and a cross bar portion that is coupled to the base portion and is substantially parallel to the longitudinal axis of the core.
11. The device of claim 10 , wherein when the actuator element is not flexed, the cross bar portions of the plurality of ribs are not in contact and when the actuator element is flexed, the cross bar portions of at least two adjacent ribs of the plurality of ribs are in contact.
12. The device of claim 8 , wherein each of the plurality of ribs include a base portion extending radially away from the core and a cross bar portion that is oriented substantially perpendicular to the base portion.
13. The device of claim 8 , wherein each of the plurality of ribs are substantially T-shaped.
14. The device of claim 6 , wherein the actuator element comprises:
a rigid actuator member extending through the cannulated elongate shaft; and
a flexible actuator member having a proximal end coupled to a distal end of the rigid actuator member, and having a distal end coupled to the end effector, the flexible actuator member being formed of a composite material;
wherein the rigid actuator member is configured to translate longitudinally through the cannulated elongate shaft to move the flexible actuator member relative to the cannulated elongate shaft and to change the stiffness of the flexible actuator member to actuate the end effector.
15. The device of claim 6 , further comprising an articulator element extending through the cannulated elongate shaft along the longitudinal axis, the articulator element being configured to articulate the end effector at an angle relative to the longitudinal axis of the cannulated elongate shaft.
16. The device of claim 15 , wherein the articulator element extends through the cannulated elongate shaft along one side thereof, and the actuator element extends through the cannulated elongate shaft along an opposite side thereof.