Paper 01: Capsuloligamentous Laxity is a Risk Factor for Failure in Near Track Lesions Following Arthroscopic Anterior Shoulder Stabilization

Objectives: Recurrent anterior shoulder instability after arthroscopic Bankart repair presents a challenging clinical problem, with the primary stabilization procedure often portending the best chance for clinical success. While the glenoid track concept continues to evolve, a limitation of the glenoid track is that it relies on bony anatomy without specific considerations for capsuloligamentous integrity or the effect that capsular laxity may have on the glenohumeral contact points throughout shoulder range of motion. The purpose of the study was to determine if capsuloligamentous laxity has a modifying effect on the glenoid track, specifically for on-track lesions with a small distance to dislocation (DTD) from being an off-track lesion or the so-called “near-track” lesion. This may explain why some on-track lesions are at an increased risk of recurrent instability. We hypothesized that patients with ligamentous laxity and “near track” lesions would be at increased risk of recurrent instability following arthroscopic Bankart repair. Methods: Consecutive patients with on-track Hill-Sachs lesions who underwent primary arthroscopic Bankart repair alone without remplissage for recurrent anterior glenohumeral instability between January 2007 and December 2015 at a single institution were retrospectively reviewed. Patients with less than 2-year follow up, glenoid bone loss > 20%, off-track lesions, concomitant remplissage, and atraumatic instability were excluded. Determination of shoulder laxity was based on exam under anesthesia (EUA), including anterior load and shift, posterior load and shift, and sulcus testing at the time of surgery before arthroscopy. Capsuloligamentous shoulder hyperlaxity was defined as external rotation of >85o and/or grade of 2+ or greater load and shift in two or more planes. Measurements of glenoid bone loss, Hill-Sachs interval (HSI), and glenoid track (GT) were performed based on prior described methods. DTD was calculated (DTD=GT-HSI, with DTD>0 classified as on-track lesions). Near track lesions were defined as 0