An undercutting system for preparing a region between an ilium and a sacrum for sacroiliac fusion. The undercutting system includes an insertion apparatus and a cutting assembly. The cutting assembly is operably mounted with respect to the insertion apparatus. The cutting assembly has a distal end and a proximal end. The cutting assembly includes a plurality of cutting elements and a cutting element attachment mechanism. The cutting element attachment mechanism engages the cutting elements to operably mount the cutting elements with respect to the insertion apparatus. The cutting element attachment mechanism permits the cutting elements to pivot with respect to each other.