The role of radiological subacromial distance measurements in the subacromial impingement syndrome

Subacromial impingement is one of the most common causes of painful shoulder in the middle aged and elderly population. Since Neer’s first description of the process, many investigators have researched this condition in an effort to gain a better understanding of the disease etiology. The aim of this study was to investigate the relationship between the radiological subacromial distance measurements and the subacromial impingement syndrome in a series of patients from our institution. For this purpose, 44 patients scheduled for a unilateral shoulder arthroscopy were investigated prospectively. The acromio-glenoid angle, supraspinatus-glenoid angle (from coronal MR images) and acromial index (from true anterior-posterior shoulder X-ray images) were measured as the implications of the subacromial distance, and the degree of subacromial impingement was graded according to intraoperative findings. Statistical data analysis revealed no significant correlations between the radiological measurements and the severity of subacromial impingement (p > 0.05). On the other hand, there was a significant correlation (p = 0.0049) between the patient age and subacromial impingement. These results suggest that the radiological subacromial distance measurements do not have enough clinical significance as predictive markers in the subacromial impingement syndrome.