Dynamic anterior stabilization for anterior shoulder instability: a meta-analysis and systematic review of clinical and biomechanical studies

Background: Dynamic anterior shoulder stabilization (DAS) combined with Bankart repair (BR) has gained attention for treating anterior shoulder instability (ASI) with subcritical anterior glenoid bone loss (GBL). This study aims to evaluate the clinical and biomechanical outcomes of DAS combined with BR for ASI. Methods: A comprehensive search of PubMed, Embase, and Scopus through August 2024 identified biomechanical and clinical studies assessing DAS in ASI. Reviews, surgical techniques, case reports, and abstracts were excluded. A meta-analysis was performed using a random-effects model, with using weighted mean differences (WMD) for continuous variables to compare pre-to-post treatment effects. MINORS and QuADS tools were used to assess the quality of the included studies. Results: Five biomechanical studies (60 cadaveric shoulders, GBL 10%-20%) demonstrated that DAS significantly improved anterior glenohumeral stability and load-to-dislocation compared to isolated BR, particularly in models with < 20% GBL and on-track Hill-Sachs lesions (HSL). Three clinical studies (100 shoulders, mean age ranged from 23.4 to 21, GBL 8.2%-10.5%) revealed significant improvements in Rowe scores (mean difference [WMD] = 58.7; p < 0.001) and forward elevation (WMD = 4.8; p = 0.02), with no significant changes in external or internal rotation. Return-to-sport rates were high (90% at any level, 71% at the same level), with 8% experiencing recurrent instability and 2% requiring reoperation. Conclusion: Available evidence suggests that DAS combined with BR offered significant biomechanical improvements, substantial patient-reported outcome improvements, better forward elevation, high return-to-sport rates, and a low complication profile for ASI with subcritical GBL. However, caution is advised in cases with off-track HSL and GBL of approximately 20%, where DAS offers less stability when compared to Remplissage and Latarjet and increased reoperations rates.