The present invention provides methods and devices for placing a spinal fixation rod into a rod receiving opening in a spinal anchor and installing a fastener to secure the rod to the spinal anchor. The proposed system when assembled creates a completed shoe. The cooling hole extends through the aerofoil wall to an external surface of the aerofoil at a position downstream of the leading edge such that, in use, cooling fluid from the cavity exits the cooling passage into the cooling hole as an impingement jet against the internal surface of the cooling hole in the region of the leading edge. Users are offloaded from an overloaded site to another site based upon the operating conditions. The two or more outputs are associated into one or more groups.