MR imaging after rotator cuff repair: full-thickness defects and bursitis-like subacromial abnormalities in asymptomatic subjects

Abstract

Objective: To determine the prevalence and extent of residual defects or retears and bursitis-like subacromial abnormalities on MR images after rotator cuff repair in asymptomatic subjects, and to define the clinical relevance of these findings.

Design and patients: Fourteen completely asymptomatic patients and 32 patients with residual symptoms were investigated 27-53 months (mean 39 months) after open transosseous reinsertion of the rotator cuff. Coronal T2-weighted turbo spin-echo and turbo STIR or T2-weighted fat-suppressed MR images were obtained. The prevalence and extent of residual defects or retears of the rotator cuff and bursitis-like subacromial abnormalities were determined.

Results: Residual defects or retears were detected in three (21%) and bursitis-like abnormalities in 14 (100%) of the 14 asymptomatic patients. Fifteen (47%) residual defects or retears and 31 (97%) bursitis-like abnormalities were diagnosed in the 32 patients with residual symptoms. The size of the residual defects/retears was significantly smaller in the asymptomatic group (mean 8 mm, range 6-11 mm) than in the symptomatic group (mean 32 mm, range 7-50 mm) (t-test, P = 0.001). The extent of the bursitis-like subacromial abnormalities did not significantly differ (t-test, P > 0.05) between asymptomatic (mean 28 x 3 mm) and symptomatic patients (mean 32 x 3 mm).

Conclusion: Small residual defects or retears (< 1 cm) of the rotator cuff are not necessarily associated with clinical symptoms. Subacromial bursitis-like MR abnormalities are almost always seen after rotator cuff repair even in patients without residual complaints. They may persist for several years after rotator cuff repair and appear to be clinically irrelevant.