MRI Versus Arthroscopy in the Detection of Glenoid Labral Tears of the Shoulder: A Cross-Sectional Study

Background Glenoid labral tears are a common cause of shoulder pain and instability, particularly in young and physically active individuals, and are frequently associated with recurrent dislocations and functional impairment. Accurate diagnosis is essential for appropriate management and prevention of long-term morbidity. While MRI is widely used as a non-invasive modality for evaluating intra-articular shoulder pathologies, arthroscopy remains the gold standard for definitive diagnosis. However, the diagnostic performance of conventional MRI, even at higher field strengths such as 3.0 Tesla, continues to be an area of active investigation. This study aims to assess the correlation between 3-Tesla MRI and arthroscopic findings in the detection of glenoid labral tears and to evaluate the ability of MRI to identify associated variants and coexisting shoulder pathologies. Methodology This cross-sectional diagnostic validity study included 50 patients presenting with clinically suspected labral tears. All participants underwent evaluation by a standardized 3.0-Tesla MRI of the shoulder followed by arthroscopy. Tear presence, type, and associated abnormalities were documented. Diagnostic performance parameters, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy, were calculated using arthroscopy as the reference standard. Data were analyzed using SPSS version 20. Results MRI detected labral tears in 40 (80%) patients, while arthroscopy identified tears in 43 (86%) patients. The most common tear pattern on both modalities was anteroinferior labral tear in 22 (44%) patients, followed by superior labral anteroposterior lesions. MRI demonstrated sensitivity of 90.7%, specificity of 85.7%, PPV of 97.5%, NPV of 60%, and overall accuracy of 90% for tear detection. Additional pathologies were found in 35 patients, with Hill-Sachs defect in 10 (28.6%), adhesive capsulitis in six (17.1%), and rotator cuff abnormalities in five (14.4%) patients. Conclusions MRI shows excellent diagnostic sensitivity and overall accuracy for detecting glenoid labral tears, particularly anteroinferior lesions, and serves as a reliable first-line, non-invasive modality. However, its lower NPV indicates that a normal MRI cannot reliably exclude pathology, affirming the role of arthroscopy in definitive assessment.