Biomechanical Evaluation of Suture Anchors in Shoulder Instability
Anterior shoulder instability remains a growing problem, especially in the young athletic population. Throughout the last decade, all-arthroscopic techniques have become an accepted method of performing shoulder stabilization procedures. Typically, in most episodes of traumatic glenohumeral instability, tearing of the labrum occurs, requiring repair of the torn tissue (read more about shoulder surgery) to the glenoid rim with suture anchors. In addition, it has been shown that capsular injury in combination with labral tear is required before instability occurs. Several methods of capsulolabral repair fixation have been described, including use of glenoid bone anchors with capsular plication. A number of different suture anchor repair constructs have been described, but there is no consensus regarding the optimal biomechanical construct. Additionally, there has been recent interest in knotless suture anchor fixation in shoulder arthroscopy, and some surgeons have begun applying knotless anchors for Bankart repairs. Knotless fixation devices have potential advantages because (1) they are relatively easy to use, obviating the need for an arthroscopic knot; (2) they are more efficient; and (3) they diminish the potential risk of knot abrasion within the glenohumeral joint.
The purpose of the present study was to determine the biomechanical stability (as determined by several biomechanical testing parameters) of an anterior Bankart repair with capsular plication performed with glenoid bone anchors using several different suture plication techniques. The specific aims of the study were (1) to compare the biomechanical properties of single-loaded suture anchors with simple stitch configuration to knotless suture anchors (no stitch) without cyclical loading and (2) to compare the biomechanical properties with cyclical loading of single-loaded suture anchors with simple stitch configuration, single-loaded suture anchors with horizontal mattress stitch configuration, double-loaded suture anchors with simple stitch configuration, and knotless suture anchors (no stitch). Our null hypothesis was that there would be no biomechanical differences between the different repair constructs.