Biomechanical properties of labral repair: simple versus vertical suture pattern

The goal of this study was to evaluate contact area and surface pressure as a result of different suture patterns in the treatment of anterior shoulder instability caused by a Bankart lesion. Loads were applied through the humeral head to the glenoid surface in the intact shoulder and after simple suture labral repair (n=10) and vertical mattress labral repair (n=9). Peak contact pressure, mean contact pressure, and contact area were recorded for 0°, 45°, and 90° shoulder abduction, and then the repair was loaded to failure. A significant increase (P<.05) in mean contact pressure and peak contact pressure occurred in both repair groups at 90° abduction. No difference was seen between the 2 repair groups. Total contact area significantly decreased after both repairs at 90° abduction at 220 N force (P<.05). No significant difference occurred in load to failure between the groups. Joint loading properties can be affected by alterations in contact pressure within the glenohumeral joint. In the current study, the authors found no significant difference in contact pressure between the 2 repair groups. However, they found a significant increase in mean contact pressure and peak pressure between the intact specimen and the 2 repair groups. Both simple repair and vertical mattress repair provided similar load to failure for labral repair. Current techniques used to perform Bankart repair may need to be altered to provide the stability of current techniques with more normal glenohumeral joint contact pressure.