RETRO-CUTTING INSTRUMENT WITH ADJUSTABLE LIMIT SETTING

摘要

Cutting instruments and related methods are disclosed herein in which the diameter of the retrograde cutting blade can be adjusted to any of a plurality of diameter settings, allowing the same instrument to be used to form holes of different diameters. The limit diameter can be preset such that, during the cutting operation, the user need not be concerned with selecting the appropriate diameter, but rather can simply deploy the cutting blade until the preset limit is reached. Cutting instruments are also disclosed in which the retrograde cutting blade is distinct from the forward drilling tip and protected within a cavity formed in the body of the instrument when not in use, as are instruments in which the user is given visual and/or tactile feedback to confirm desired positioning of the cutting blade.

主权项

1. A cutting instrument, comprising:
an elongate body having proximal and distal ends, the distal end defining a drilling tip; a cutting blade pivotally disposed within a cavity formed in the elongate body such that the cutting blade is positionable in a retracted position in which the cutting blade does not protrude from the elongate body and one or more deployed positions in which the cutting blade protrudes from the elongate body; an actuation shaft extending through the elongate body and having a distal end coupled to the cutting blade such that longitudinal translation of the actuation shaft relative to the elongate body is effective to move the cutting blade between the retracted position and the one or more deployed positions; an actuation knob coupled to the actuation shaft such that rotation of the actuation knob about a longitudinal axis of the elongate body is effective to longitudinally translate the actuation shaft relative to the elongate body; and an adjustment element configured to limit the degree to which the actuation shaft can be longitudinally translated relative to the elongate body based on a position of the adjustment element relative to the elongate body.