Patent ID: 7320700
Filing Date: 2008-01-22
Classification: A61B

Abstract:
1. 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; an end effector; a wrist member having a flexible tube and an inner spring, the flexible tube including a proximal portion connected to the working end of the elongate shaft and a distal portion connected to the end effector, the inner spring including a proximal portion connected to the workig end of the elongate shaft and a distal portion connected to the end efector, the inner spring being disposed inside an interior cavity of the flexible tube, the inner spring having an axis which is parallel to an axis of the flexible tube; and a plurality of actuation cables having distal portions connected to the end effector and extending from the distal portion through the wrist member toward the elongate shaft to proximal portions which are actuatable to bend the flexible tube and the inner spring of the wrist member so as to allow pitch rotation and yaw rotation of the end effector; wherein the inner spring is in the form of a wire wrap that is wrapped around the plurality of actuation cables in a coil spring fashion.