Arthroscopic and MRI Visibility of the Rotator Cable in Supraspinatus Tears: Agreement, Associated Factors, and Relationship with Preoperative Range of Motion

Abstract

Background: The rotator cable is thought to contribute to load transmission and preservation of shoulder function in rotator cuff tears; however, its detectability on arthroscopy and magnetic resonance imaging (MRI), agreement between these modalities, and clinical relevance remain incompletely defined. This study evaluated rotator cable visibility on arthroscopy and MRI, factors associated with arthroscopic cable visibility, and its relationship with preoperative active shoulder motion. Methods: This retrospective cross-sectional study included 128 patients who underwent shoulder arthroscopy for supraspinatus tears between January 2019 and February 2023. Arthroscopic video recordings were reviewed for rotator cable visibility. Standardized preoperative MRI review was available in 58 patients. Agreement between MRI and arthroscopic visualization was assessed using Cohen’s kappa and percentage agreement measures. Multivariable binary logistic regression was performed to identify factors independently associated with arthroscopic cable non-visibility. Results: The rotator cable was visible arthroscopically in 79 of 128 patients (61.7%) and on MRI in 38 of 58 patients (65.5%). Overall agreement between MRI and arthroscopy was 67.2% (95% CI, 53.7–79.0%), with a Cohen’s kappa of 0.315 (95% CI, 0.090–0.540; p = 0.011), indicating fair agreement. Positive and negative percent agreement were 78.8% and 52.0%, respectively. Although increasing age was associated with cable non-visibility in univariable analysis, this association did not remain statistically significant after multivariable adjustment. Higher Lafosse grade was independently associated with cable non-visibility in the overall cohort (adjusted OR, 1.43 per grade; 95% CI, 1.04–1.97; p = 0.028), whereas increasing tear size was independently associated with cable non-visibility among patients with full-thickness tears (adjusted OR, 2.78 per category; 95% CI, 1.19–6.52; p = 0.019). The unadjusted association between massive tear size and reduced MRI cable visibility did not remain significant after false discovery rate adjustment (q = 0.276). No statistically significant associations were detected between cable visibility or MRI-measured cable dimensions and preoperative active abduction or forward elevation. Conclusions: MRI and arthroscopy demonstrated fair agreement in the assessment of rotator cable visibility. After multivariable adjustment, cable non-visibility was more closely associated with tear-related characteristics than with patient age. No statistically significant associations were detected between cable characteristics and the assessed preoperative range-of-motion measures; however, smaller or moderate associations cannot be excluded, particularly within the MRI subgroup. Rotator cable visibility should primarily be interpreted as a marker of detectability and tear morphology rather than as a direct surrogate for structural integrity or shoulder function.