Does the use of a tensioning device improve stability for suture fixation of glenoid bone constructs? A biomechanical analysis.

PURPOSE

The purpose of this study is to quantify the difference in biomechanical stability of suture button (SB) and suture tape cerclage (STC) constructs with hand tensioning versus device tensioning of anterior glenoid augmentation bone grafts in an anterior glenoid bone loss model.

METHODS

Artificial bone blocks with a density of 15 lb/ft (240.3 kg/m) were used as models for glenoid fixation with bone graft. The biomechanical stability of SB and STC tensioned by hand was compared to those tensioned by a device. Average displacement (mm) following application of various forces (50, 100, 150, and 200 N) during a 7-phase, 100-cycle, stairstep cyclic loading protocol was recorded.

RESULTS

Both SB and STC fixation displayed significantly lower construct displacement at all tested forces when tensioned with a device versus hand ( < 0.001). Device-tensioned SB and STC were comparable in construct stability at forces below 100N. However, at forces above 100 N, device-tensioned SB exhibited significantly less displacement than device-tensioned STC.

DISCUSSION

Using a tensioning device for SB or STC fixation of a coracoid graft model results in less displacement and improved stability compared to hand tensioning. Biomechanically, a tensioning device enhances the stability of suture fixation in glenoid bone graft constructs.