Summary

Capsuloligamentous laxity is a significant independent risk factor for failure after arthroscopic Bankart repair, and hyperlaxity may increase the failure risk in younger patients with a small distance to dislocation.

Abstract

Introduction

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. 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 who underwent primary arthroscopic Bankart repair for recurrent anterior glenohumeral instability with at least 2-year follow-up at a single institution between 2007-2019 were retrospectively reviewed. Patients with glenoid bone loss > 20%, off-track lesions, concomitant remplissage, or rotator cuff tear were excluded. Capsuloligamentous laxity, or hyperlaxity, was defined as external rotation >85 degrees and/or grade 2+ or greater load-and-shift in two or more planes.

Results

173 consecutive patients with mean age of 20.5 years and mean DTD of 16.2 were included for analysis. 16.8% sustained a recurrent dislocation and 6.4% had recurrent subluxations (defined as any subjective complaint of recurrent instability without frank dislocation), with an overall recurrent instability rate of 23.1%. The rate of revision stabilization was 15.6%. Mean time to follow-up was 7.4 years. Independent predictors of recurrent instability were younger age (p = 0.001), smaller DTD (p = 0.021), >1 instability episode pre-op (p = 0.001), and presence of hyperlaxity on EUA (p = 0.013). Among patients with near-track lesions, those with hyperlaxity had a recurrent instability rate almost double those without hyperlaxity (OR 34.1, p = 0.036). The increased rate of failure and recurrent dislocation in the near-track hyperlaxity cohort remained elevated, even in patients with no bone loss.

Discussion

Capsuloligamentous laxity is a strong independent risk factor for failure after arthroscopic Bankart repair alone and is an even greater risk factor in patients with a small DTD. As our understanding of the glenoid track continues to evolve, surgeons may need to consider the track concept as a continuum and consider surgical algorithms other than an arthroscopic Bankart alone in patients with near-track lesions and hyperlaxity at time of surgery.