Patent ID: 8142464

Claim:
An angled rotary tissue cutting instrument for cutting anatomical tissue, comprising an elongate angled outer tubular member having a distal end, a longitudinal internal passage, an open proximal end communicating with said passage, an angled region between said distal end and said proximal end, and an opening in said distal end communicating with said passage; and a flexible inner member for being rotatably disposed within said outer tubular member, said inner member having a distal end, a proximal end, a tubular body between said distal end of said inner member and said proximal end of said inner member, a cutting element at said distal end of said inner member, said cutting element being exposed from said opening to cut anatomical tissue when said inner member is rotatably disposed within said outer tubular member, and a flexible region for being disposed within said angled region to transmit torque to rotate said cutting element while conforming to the configuration of said angled region when said inner member is rotated within said outer tubular member, said tubular body having a central longitudinal axis and a cylindrical wall with an external circumferential surface, an internal circumferential surface, a wall thickness between said external circumferential surface and said internal circumferential surface, and an external circumference defined by said external circumferential surface, said flexible region comprising a series of disconnected partial circumferential cuts formed in said wall of said tubular body entirely through said wall thickness, each of said cuts extending along an arc in a rotational direction about said central longitudinal axis from a first end of said cut to a second end of said cut, said arc of each of said cuts forming part of said external circumference of said tubular body and being disposed in a plane perpendicular to said central longitudinal axis of said tubular body, said planes of said cuts being parallel to one another in uniform spaced relation along the length of said flexible region, said cuts being arranged on said tubular body in repeating patterns of rotational offset along the length of said flexible region, each of said patterns comprising a first cut, a second cut in adjacent longitudinal succession from said first cut, and at least a third cut in adjacent longitudinal succession from said second cut, said first ends of said second cuts being rotationally offset from said first ends of said first cuts in said rotational direction about said central longitudinal axis by a rotational offset, and said first ends of said third cuts being rotationally offset from said first ends of said second cuts in said rotational direction about said central longitudinal axis by said rotational offset.