A method of repairing a prior sacroiliac fusion that was not effective at stabilizing a sacroiliac joint. The prior sacroiliac fusion used a first fastening device that extended between an ilium and a sacrum. At least one aperture is formed that at least partially extends through at least one of an ilium and a sacrum. An undercutting system is inserted at least partially into the aperture and is used to cut tissue between the ilium and the sacrum. A second fastening device is inserted into the first aperture to retain the ilium in a stationary position with respect to the sacrum.