Self-boring anchoring device and method of installing such an anchoring device

A method of installing a fixation device into a substrate, the fixation device comprising a shaft rotatable about a longitudinal axis having a first cutter at a first, distal end;

• a guide body on the shaft shaped to taper outwardly towards the first end of the shaft;
• an elongate sleeve disposed surroundingly about the shaft to be rotatable separately from the shaft and translatable in a longitudinal direction relative to the shaft;
• and a flareable end formation at a first, distal end of the elongate sleeve comprising one or more second cutters, wherein the elongate sleeve is provided in two parts comprising a distal part and a proximal part axially spaced apart, the two parts are co-rotated as the sleeve is translated laterally, and the two parts are then caused to move axially closer together as the shaft is urged relative to the sleeve back towards the second end of the sleeve;
• the method comprising the steps of:
• rotating the shaft and thereby boring a hole into a substrate using the first cutter;
• translating the sleeve in a longitudinal direction distally relative to the shaft to urge the flareable end formation over the guide body and flare the end formation outward from the shaft;
• rotating the sleeve and thereby reaming out an undercut in the substrate;
• and
• urging the shaft relative to the sleeve back towards the second end to apply a tension to the shaft.