Patent ID: 7569057
Filing Date: 2009-08-04
Classification: A61B

Abstract:
1. A powered, hand-held instrument for treating vertebral endplates, comprising: a body configured to be held in a surgeon's hand; a camshaft rotatable about a rotational axis in said body and having a cam surface rotatable about said rotational axis; a cutter shaft having a proximal end and a distal end, said cutter shaft extending along a longitudinal axis and being mounted in said body to reciprocate in forward and reverse directions along said longitudinal axis; a cutter disposed at said distal end of said cutter shaft and configured to have a preferred performance direction in one of said forward and reverse directions; said cutter shaft being moveable in said preferred performance direction by said cam surface when said camshaft is rotating; a cutter drive shaft having a proximal end and a distal end, said cutter drive shaft having a first connector at said distal end and a cam follower surface adjacent said proximal end and facing said cam surface; said cutter engaged to said cutter shaft and having a reverse preferred performance direction, said cutter shaft having a second connector at said proximal end of said cutter shaft, said second connector connected to the first connector to transmit axial force between said cutter drive shaft and said cutter shaft; and means for normally disabling movement of said cutter shaft by said camshaft, said means for disabling being a compression spring bearing on said body and on a portion of said cutter drive shaft to urge said cam follower surface in a reverse direction away from said cam surface.