MRI-based assessment of greater tuberosity exposure in massive rotator cuff tears: a systematic review of current evidence and methodological gaps

Abstract Background Massive rotator cuff tears (MRCTs) lack a standardized and reproducible imaging-based definition. A recent Delphi consensus introduced greater tuberosity exposure (GTE) as a defining criterion for MRCTs, proposing that MRCTs be classified by either involvement of at least two rotator cuff tendons or ≥ 67% GTE on magnetic resonance imaging (MRI). Purpose To evaluate the role of GTE in the MRI-based definition and structural characterization of MRCTs and to describe the extent and methodological maturity of the evidence available for GTE and established MRI-derived parameters. Methods A systematic literature search was conducted in PubMed/MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials from database inception to February 17, 2026, and updated on October 9 and 11, 2026 with supplementary citation searching, in accordance with PRISMA 2020 guidelines. Studies were included if they investigated MRCTs using MRI-based or MRI-transferable imaging and reported structural definitions, measurement methods, or associations with irreparability, structural healing, or clinical outcomes. Prognostic studies were assessed using the Quality In Prognosis Studies (QUIPS) tool. Findings were synthesized narratively; no meta-analysis was performed due to substantial heterogeneity in study designs, imaging protocols, and outcome definitions. The synthesis described the extent and methodological maturity of the available evidence and did not compare diagnostic or prognostic performance between parameters. Results A total of 34 studies were included. No study evaluated GTE as a quantitative MRI-derived parameter. Only two studies addressed footprint coverage on imaging, one qualitatively and one by a semi-quantitative five-zone score of residual tendon attachment; neither measured GTE as a defined exposure parameter or applied predefined thresholds. In contrast, MRCTs were consistently characterized using indirect structural parameters, primarily tendon involvement and tear size. Established MRI-derived variables—including tear size, tendon retraction, fatty infiltration, muscle atrophy, and superior humeral migration—were assessed using established measurement frameworks based on defined anatomical landmarks, notwithstanding methodological heterogeneity in imaging protocols and thresholds across studies. These parameters were frequently evaluated in relation to irreparability, structural healing, and functional outcomes, whereas no study evaluated a direct quantitative MRI-based measure of GTE in relation to a clinical or structural endpoint. Conclusion No standardized and outcome-validated MRI-based method for quantifying GTE was identified within the scope of this review. Despite its conceptual appeal as a direct representation of footprint deficiency, GTE has not yet undergone standardized measurement development or outcome-based validation. The evidence base for established MRI-derived parameters is more extensive and methodologically mature, with operationalized measurement methods and reported outcome associations; this does not imply clinical inferiority of GTE. Future research should focus on developing reproducible MRI-based measurement techniques for GTE and evaluating its diagnostic and prognostic relevance in dedicated validation studies. Study design Systematic review; Level of evidence, 3. Individual included studies ranged from Level II to Level V.