Relationship Between Rotator Cuff Tears and Scapular Morphology

Abstract Background The purpose of this study was to identify differences in the morphology of the scapula according to the presence or absence of a rotator cuff tear (RCT). Methods One hundred and three shoulders with and 87 shoulders without RCTs were included in this study. The critical shoulder angle (CSA) and lateral acromion angle in the frontal view and the acromial coverage angle (ACA) and coracoid and scapular spine angle (CSSA) in the lateral view were evaluated using three-dimensional computed tomography. The glenoid anterior tilt, anterior acromial projection angle (AAPA), coracoid process angle, scapular spine angle (SSA) and inferior angle angle (IAA) with respect to the scapular plane were measured in the lateral view. The morphological parameters of the scapula associated with RCT were statistically analysed using a multivariate logistic regression analysis. Results In univariate logistic regression analysis, CSA, ACA, CSSA, AAPA, SSA and IAA were significantly different between shoulders with and without RCTs. In multivariate logistic regression analysis, CSA and IAA were greater in shoulders with RCT and were significantly associated with this condition. Conclusion To the best of our knowledge, this is the first study to focus on the relationship between RCT and the scapular body. RCT cases were characterised by a greater curvature of the scapular body in addition to CSA.