MR evaluation of rotator cuff impingement: correlation with confirmed full-thickness rotator cuff tears.

OBJECTIVE

To clarify the efficacy of MRI for the evaluation of rotator cuff impingement beneath the coracoacromial arch, MRI findings were correlated with confirmed full-thickness rotator cuff tears (FTRCTs).

MATERIALS AND METHODS

Thirty-four shoulders with FTRCT and 49 control shoulders without FTRCT were selected for this study. Direct measurement of the subacromial space (SAS) and MRI grading of SAS and subacromioclavicular space (SACS) were correlated with FTRCT. In addition, the MRI impingement score (sum of SAS grade and SACS grade) was correlated with age and FTRCT.

RESULTS

Direct measurement of the SAS showed poor correlation with FTRCT. The SAS grade showed significant correlation with FTRCT; however, SACS grade showed poor correlation. Shoulders with higher MRI impingement scores were associated with FTRCT in patients over 40 years of age.

CONCLUSION

The MRI sign of rotator cuff impingement is fairly reliable and helpful in discriminating patients with FTRCT, especially older patients.