Patent ID: 8052710
Filing Date: 2011-11-08
Classification: A61B

Abstract:
1. An instrument for surgical dissection of tissue comprising: an elongated tube having proximal and distal ends, the tube having an internal passage, extending along a central axis, for insertion of an instrument through the tube and a substantially cylindrical external surface symmetrical about said central axis; plural retractor blades, each said blade extending in a distal direction from a location adjacent the distal end of the elongated tube and being pivoted for rotation about a pivot axis adjacent said distal end of the elongated tube, the pivot axis about which each of said blades is pivoted being disposed, at a fixed location relative to the distal end of the elongated tube, in a plane to which said central axis is perpendicular; and an adjuster rod connected to each blade at a connecting location spaced from the blade's pivot axis in a radial outward direction with respect to said central axis, each adjuster rod extending proximally at least part way through the elongated tube, and being accessible at a location adjacent the proximal end of the tube, said adjuster rods being movable longitudinally, restricted in their longitudinal movement to movement along axes of movement extending in parallel and fixed relation to said central axis, and movable along said axes of movement independently of one another for independent pivoting adjustment of each of said retractor blades about its pivot axis; said blades having outer, tissue-engaging, surfaces which face in opposite directions and are convex throughout substantially their entire lengths in said distal direction in cross-sectional planes to which said distal direction is perpendicular, and having inner surfaces which are concave throughout substantially their entire lengths in said cross-sectional planes; and said blades are adjustable, by pivoting about said pivot axes, to positions in which they are all substantially within an axial projection of the substantially cylindrical external surface of the tube but substantially entirely external to an axial projection of said internal passage, and to positions in which parts of their outer, tissue-engaging, surfaces are external to said substantially cylindrical external surface.