Abstract: A tool centers an elongated drill bit within an elongated canal surrounded by bone tissue. A sleeve having an expandable diameter is internally threaded. The sleeve threadedly engages an externally-threaded cylindrical guide. A key includes a handle at one end of an elongated rod. The rod includes transversely-protruding buttons for engaging the guide so that rotation of the handle produces rotation of the guide to cause radial expansion of the sleeve. This results in symmetrical contacting of the interior surfaces of the bone tissue, thereby creating a vertical, centered channel with respect to the bone, that extends through the tool for guiding the drill bit.

Abstract: A tool for guiding a surgical drill bit through the center of a target obstruction within a bone. An adjustable frame includes a pair of right angle sections mounted in a mirror image relationship. The sections are adjustably clamped to one another and, in turn, secure a vertical sleeve for guiding a surgical drill bit and a horizontal sleeve for accommodating an anchor pin within a coplanar arrangement. Various clamps associated with the frame elements and the sleeves permit a surgeon to adjust the tool so that the drill bit is guided through the vertical sleeve to the approximate center of the bone immediately below the obstruction while the pin anchors the frame to the bone.