Tissue cutter

Claim 1

A tissue cutter for surgical purposes, said tissue cutter having a proximal and a distal end, and comprising: a support; an outer tube mounted to said support having a central axis, an internal axially extending passage, and a first cutter blade at its distal end; an operating rod in said passage and axially reciprocable therein; a second cutter blade carried by said operating rod and reciprocable thereby, whereby in one axial position of said rod said second cutter blade projects distally beyond said first cutter blade, and in another axial position it is drawn into said passage, having made a close tissue-cutting pass through said first cutter blade so as to cut tissue disposed between them; a stripper rod in said passage and axially reciprocable therein, said stripper rod being adapted to be moved into said outer tube when said second cutter blade is moved into said outer tube, and selectively to remain in said outer tube when said second cutter blade is moved out of said outer tube; a stripper carried by said stripper rod and its distal end, adapted either to be outside of said outer tube or to be inside of said outer tube when said first cutter blade is outside said tube and to move tissue cut by said blades into said passage; bias means biasing said stripper rod toward a position where said stripper is outside of said outer tube; releasable latch means for restraining said stripper rod with said stripper inside said outer tube in opposition to said bias means; and handle means pivotally mounted to said support for reciprocating said operating rod, said operating rod and stripper rod occupying less than the total cross-section of said passage near its distal end, whereby to receive plural cuttings of tissue, whereby when said operating rod is moved toward the proximal end and the cutters pass one another, a tissue cutting is moved into said outer tube by said stripper, and said stripper rod is latched so that the stripper is inside said outer tube, after which said handle means can be moved to permit said first cutter to return to its most distal position, release of said latch means enabling said stripper rod to be moved abruptly by said bias means in the distal direction to leave said tissue cutting inside said outer tube at a location spaced from said distal end of said outer tube as a consequence of the inertia of said tissue cutting.