Sensitivity of preoperative magnetic resonance imaging and magnetic resonance arthrography in detection of panlabral tears of the glenohumeral joint.

Abstract

The purpose of this study was to evaluate the sensitivity of preoperative magnetic resonance imaging (MRI) in detecting combined lesions of the glenoid labrum involving tears of the anterior, posterior, and superior labrum. Preoperative MRI findings were available in 46 cases of arthroscopic repair of combined tears of the anterior, posterior, and superior labrum (mean age, 31 years), including 23 noncontrast MRI studies and 24 magnetic resonance (MR) arthrography studies (1 patient had both). MRI findings were compared with the status of the labrum at the time of arthroscopy, and the sensitivity of MRI was determined. MRI showed evidence of combined lesions of the anterior, posterior, and superior labrum in only 10 of 47 studies (21.3%). Only 2 of 23 (8.7%) tears were detected by noncontrast MRI, compared with 8 of 24 (33.3%) by MR arthrography (P = .07). Non-contrast MRI showed evidence of labral pathology in more than one direction in 10 of 23 studies (43.5%), compared with 20 of 24 MR arthrography studies (83.3%) (P = .006). Noncontrast MRI showed no evidence of a labral tear in 3 of 23 patients (13.0%), whereas no MR arthrogram was completely negative for a labral tear (0%) (P = .11). Combined tears of the anterior, posterior, and superior glenoid labrum are infrequent injuries that are typically not completely defined by either noncontrast MRI or MR arthrography. Level III, diagnostic study.