Biomechanical Strength of Screw Versus Suture Button Fixation in the Latarjet Procedure: A Cadaver Study

We compared the strength of screw vs suture button fixation in the Latarjet procedure for shoulder dislocation through biomechanical testing in a cadaver model. Cadavers were assigned randomly to receive screw or suture button fixation (both groups, n=5). The anteroposterior radius of the glenoid was measured, and a bony defect was created on the anteroinferior rim of the glenoid, equal to 25% of the width of the anteroposterior radius of the glenoid surface. The coracoid process was transferred into the newly created bony defect of the glenoid and fixed with two 3.5-mm partially threaded cannulated screws or 2 surgical buttons. All samples underwent tensile testing in the anteroinferior direction. Statistical analysis was performed to compare mean forces at failure between groups (alpha=.05). The mean force at failure was higher in the screw group (295 N; range, 103- 534 N) than in the suture button group (133 N; range, 74-270 N) (P=.045). We found no difference between groups in ability to withstand a force of 150 N, which is the reported mean daily force threshold borne by the shoulder (P=.52). Screw fixation withstood a higher failure load than suture button fixation, indicating that screw fixation is a biomechanically superior option in the Latarjet procedure. The fixation methods did not differ in their ability to withstand the mean force borne by the shoulder during activities of daily living; thus, suture button fixation should be considered as an option in the Latarjet procedure.