Abstract: A generally cylindrical broken bone screw removal device having a trephine assembly located at the distal end and a proximal end adapted to be engaged by a tool for rotating the device. The trephine assembly has a trephine, an alignment pin, and an internal annular cam. The cam is free to rotate independent of the trephine. The internal wall of the cam has a D shaped cross-section which is tapered, i.e. decreases in size from the distal toward the proximal end of the device. The internal diameter of the trephine is eccentric to its outer diameter, and the D shaped cross-section of the cam is eccentric to the internal diameter of the trephine.

Abstract: A tool which has a tip with sharp edges and which is adapted to be inserted into the recess of the head of a stripped socket head screw. Once in the recess the tool is rotated to cause tip edges to bite into the internal wall of the recess, so that enough torque can be applied by the tool to the screw head to rotate the screw out of an object with which it is threadably engaged. In one embodiment the tip has an eccentric camming configuration. In a second embodiment it has a split end configuration with the two parts of the end being slidably movable with respect to each other. In a third embodiment the tip has a helical tapered configuration with a polygonal cross-section having sharp facet edges.