BIOMECHANICAL STUDY OF THE SACROILIAC FRACTURE FIXATION WITH TITANIUM RODS AND PEDICLE SCREWS

Objectives: To assess biomechanically different fixations means of the sacroiliac joint with pedicle screws and to compare the traditional head height with reduced ones. Methods: We used a polyethylene model representing the pelvic ring and simu-lated a unilateral sacroiliac dislocation. We set up three different constructions: 1) two screws attached to a rod; 2) two rods connected to two small head screws each; and 3) two rods connected to two average headed screws each. We conducted tests in a biomechanical testing and a mechanized processing laboratory. Results: Group 1 supported an average maximum load of 99.70 N. Group 2 supported an average maximum load of 362.46 N. Group 3 endured an average maximum load of 404.15 N. In the assembly with one rod, the resistance de-creased as compared with the one with two bars: 72.5 % com-pared to small-headed screws and 75.3 % to the traditional screw. Conclusion: The assembly with a single bar presented inferior results when compared to the double bar assembly. There was no statistical difference in the results between the screws used. Experimental Study