The sacral-iliac joint between an iliac and a sacrum is fused either by the creation of a lateral insertion path laterally through the ilium, through the sacral-iliac joint, and into the sacrum, or by the creation of a postero-lateral insertion path entering from a posterior iliac spine of an ilium, angling through the sacral-iliac joint, and terminating in the sacral alae. A bone fixation implant is inserted through the insertion path and anchored in the interior region of the sacrum or sacral alae to fixate the sacral-iliac joint.
