Accuracy of magnetic resonance imaging of the shoulder in evaluation of anterior shoulder instability

Abstract

Background: Shoulder arthroscopy is currently considered the gold standard in diagnosing shoulder pathologies. Although magnetic resonance imaging (MRI) has an established accuracy in determining labral injuries following glenohumeral instability, the opinions of surgeons and radiologists regarding MRIs are still inconsistent till date. The aim of this study was to carry out a diagnostic evaluation of MRI vis-a-vis shoulder arthroscopy for the assessment of Bankart and Hill-Sachs lesions in subjects of anterior shoulder instability. Subjects and Methods: This was a diagnostic evaluation study, estimating the accuracy of MRI in diagnosing lesions encountered in shoulder dislocations vis-a-vis shoulder arthroscopy. Ninety participants of anterior shoulder dislocation were evaluated preoperatively with a shoulder MRI. The study participants were later subjected to a diagnostic shoulder arthroscopy and managed operatively on a case-to-case basis. Results: The sensitivity and specificity of MRI to diagnose a Bankart lesion were 90.78% and 85%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) were 97% and 63% for the same. The sensitivity and specificity of MRI to diagnose a Hill–Sachs lesion were 92.68% and 85.71%, respectively. The PPV and NPV were 84.44% and 93.33% for the same. The diagnostic accuracy for MRI detection of Bankart lesion was 91% and of Hill–Sachs lesion was 88.89%. Conclusions: MRI is a very sensitive and specific tool in the detection of lesions commonly associated with shoulder instability, namely Bankart and Hill–Sachs lesions.