MR arthrography evaluation in patients with traumatic anterior shoulder instability

Introduction To evaluate retrospectively the diagnostic accuracy of MR arthrography, compared with arthroscopy, in research of the glenoid labrum tear in patients with a first episode of traumatic anterior shoulder instability (TUBS). Material and methods We retrospectively reviewed the MR arthrography shoulder images of 118 patients with a first episode of TUBS, between June 2014 and May 2016. Results The overall accuracy of MR arthrography compared with arthroscopy of the glenoid labrum lesions was 94%, sensitivity 93%, and specificity 96%. The sensitivity of MR arthrography for Perthes lesion was 71.4%, and for ALPSA lesion, it was 91%. Slap lesion occurred in 11 out of 77 cases (9.3% of 118 cases). The Hill-Sachs lesion occurred in 48 out of 118 cases (40.7%), while the Hill-Sachs reverse lesion in 4 cases (3.4%). Conclusions The MR arthrography is accurate in detecting labral injuries. However, other studies are needed to assess the less frequent tear, as Perthes lesion. The presence of the Hill-Sachs lesion could provide useful information about the level of the shoulder instability.