Radiographic characteristics of the acromion process as a predictive factor of partial rotator cuff tears

Abstract

Injuries of the shoulder joint make up to 55 % of all large joint injuries, among which the rotator cuff tears is the most common. Partial rotator cuff tears diagnosis is a difficult task for the traumatologist. Purpose of this study is evaluation radiographic characteristics of the acromion in patients with partial rotator cuff tears. Material and methods Fourteen patients with verified partial rotator cuff tears and 14 patients with chronic instability of the shoulder joint were selected for retrospective analysis of illness history data and radiological results. The first (index) group consisted of 11 men and three women; the second (control) group consisted of 13 men and one woman. Patients with partial rotator cuff tear had it from the subacromial space. Radiographs of the shoulder joint were taken in standard projections (anteroposterior, Y-shaped) in this study. The following criteria were evaluated: lateral acromial angle (LAA), acromial index (AI), critical angle of the shoulder joint (CSA), size of the subacromial space and type of acromial process according to Bigliani. Results Significant age difference was found between the groups. There was no statistical difference between groups in LAA and AI. For CSA and size of the subacromial space, a significant difference was found between the groups. Dependence on the type of the acromial process was not found; the prevalence of types 2 and 3 of the acromial process according to Bigliani in the group of partial rotator cuff tears was observed. Conclusion There is an anatomical difference between patients with rotator cuff tears and chronic instability of the shoulder joint. Significance of the criteria of the critical shoulder angle (CSA) and the size of the subacromial space as a prognostic factor in partial rotator cuff tears was proven.

Keywords

• partial tear
• rotator cuff
• shoulder joint
• critical shoulder angle