Study reveals which shoulder surgery patients are most likely to need repeat operations

IMPORTANCE: Recurrent anterior shoulder instability after arthroscopic Bankart repair remains a relevant clinical challenge, with reported failure rates up to 30% at long-term follow-up. Several risk stratification tools, particularly the Instability Severity Index Score (ISIS) and the Glenoid Track Instability Management Score (GTIMS), have been widely adopted in clinical practice; however, the independent contribution of their individual prognostic factors has not been comprehensively evaluated using contemporary evidence. AIM: To systematically assess and quantify the associations between individual prognostic factors included within the ISIS and GTIMS frameworks and recurrence after arthroscopic Bankart repair. EVIDENCE REVIEW: A systematic search of MEDLINE, Embase, LILACS, and Epistemonikos was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and meta-analysis of observational studies in epidemiologyguidelines. Observational analytical studies evaluating prognostic factors for failure after arthroscopic Bankart repair were included, with a specific focus on variables incorporated into the ISIS and GTIMS frameworks, which are commonly used to guide clinical decision-making. Data extraction followed Checklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies - Prognostic Factors recommendations and risk of bias was assessed using the Quality in Prognostic Studies tool . Meta-analyses using Mantel-Haenszel methods were conducted, reporting pooled odds ratios (ORs) with 95% confidence intervals (CIs). FINDINGS: Twenty-nine studies involving 11,038 patients were included, with a pooled recurrence rate of 13.34% (1471 failures). Among the individual components incorporated into the ISIS and GTIMS frameworks, the factors most consistently and strongly associated with recurrence were age <20 years (odds ratio [OR]: 2.14; 95% CI: 1.23-3.39, p < 0.001), participation in competitive sports (OR: 2.73; CI: 95% 1.11-6.73, p: 0.002), contact sports (OR: 1.65; 95% CI: 1.14-2.83, p: 0.007), presence of Hill-Sachs lesions on radiographs (OR: 2.63; 95% CI: 1.66-4.16, p < 0.001), and off-track lesions (OR: 4.35; 95% CI: 2.18-8.69, p < 0.001). Hyperlaxity showed a non-significant association (OR: 1.76; 95% CI: 0.98-5.21), with substantial heterogeneity across studies. Radiographic glenoid bone loss did not reach statistical significance (OR: 2.97; 95% CI: 0.96-9.25). Overall methodological quality of the included studies was moderate, with recurrent concerns related to prognostic factor measurements, outcome definition, and adjustment for confounding. CONCLUSION: Recurrence after arthroscopic Bankart repair is influenced by multiple interacting factors. Among the individual components incorporated into the ISIS and GTIMS frameworks, age <20 years, competitive and contact sports, presence of radiographic Hill-Sachs lesions, and off-track status showed the most consistent and strongest associations with failure. These findings support a nuanced interpretation of existing instability scores, in which patient age, sports exposure, and bone loss characteristics are integrated into preoperative decision-making, rather than reliance on rigid score cutoffs alone. LEVEL OF EVIDENCE: Level III-Systematic review of prognostic cohort and case-control studies.