Adjustable drill gauge

A drill assembly for forming a hole of a specified depth in a bone for receiving a fracture-reducing implant, the assembly comprising,

• a drill bit having an elongated shaft and a drilling end, the shaft including a plurality of circumferentially extending, axially spaced grooves formed thereon,
• a stop member formed to include an axially extending bore sized to receive said shaft of said drill bit to permit said stop member to be moved axially along said shaft, and
• a plunger configured to releasably engage one of said shaft grooves at a selected location along said shaft, the plunger being movable in said stop member along a plane substantially perpendicular to said shaft to releasably lock said stop member against movement along said shaft to define an operable portion of the drill bit between the stop member and the drilling end of the drill bit, the plunger being movable in response to a force applied along an axis that is substantially perpendicular to an axis defined by the stop member bore.

A drill bit stop apparatus for use with a drill bit having an elongated shaft defining a first axis and having a cutting end and a plurality of circumferentially extending, axially spaced grooves formed thereon, the apparatus comprising,

• a body member having a first end and configured to be slidably received for movement over said elongated shaft along said first axis, and
• finger operated plunger means disposed within said body member for releasably engaging one of said plurality of said shaft grooves to lock said body member against movement along said first axis on said shaft while permitting rotational movement of the body member with respect to the shaft, said plunger means movable in response to a force applied along an axis substantially perpendicular to the first axis between a groove-engaging position and a groove-disengaging position, and
• spring means for yieldably urging said plunger into the groove-engaging position.

An adjustable drill stop for use with an elongated drill having circumferentially extending, axially spaced grooves formed thereon, the stop comrprising,

• a generally cylindrical housing formed to include a bore extending axially entirely through said housing, said housing also formed to include a cavity that extends into said housing through said aperture, said cavity oriented substantially perpendicular to said aperture,
• a finger-operated plunger disposed in said cavity, said plunger formed to include an opening that is sized and oriented to receive a portion of said drill bit and including a ridge formed in said opening that is configured to releasably engage one of said grooves formed on said drill bit, said plunger movable from a groove-engaged position to a groove-disengaged position by application of a plunger-depressing force applied along an axis substantially perpendicular to an axis defined by said bore, and
• a spring for releasably biasing said plunger to the groove-engaging position.