Superior labrum anterior-posterior lesions on shoulder MR arthrography / 中华放射学杂志

ABSTRACT

Objective To evaluate the diagnostic value of shoulder MR arthrography for superior labral anterior-posterior (SLAP) lesions.Methods A retrospective study was conducted in 137 cases of shoulder MR arthrography confirmed by subsequent shoulder arthroscopy.Two radiologists analyzed all MR examinations independently and the results were compared with those of arthrescopy.The superior labrum was described as normal or torn.In addition, each iabral tear was classified as type Ⅰ-Ⅳ.Type Ⅰ lesions were defined as marked fraying of the articulating surface of the superior labrum; type Ⅱ, avulsion of the labral-bicipital complex from the ghnoid; type Ⅲ, displaced bucket handle tear of the superior labrum; and type Ⅳ, bucket handle tear of the superior labrum with extension into the fibers of the biceps tendon.Sensitivity, specificity, and accuracy were calculated.Kappa values were calculated to quantify the level, of inter-observer agreement.Results SLAP lesions were arthroscopically diagnosed in 59 of the 137 patients.Six of the 59 lesions ( 10.2% ) were classified as type Ⅰ , 50 (84.7% ) as type Ⅱ, and 3 (5.1% ) as type Ⅲ.The overall sensitivity, specificity, and accuracy of MR arthrographic detection of SLAP lesions were 86.4% (51/59), 78.2% (61/78), and 81.8% ( 112/137), respectively, for observer A, and 88.1% (52/59), 84.6% (66/78), and 86.1% (118/137), respectively, for observer B.At inter-observer comparison, agreement was very good (Kappa values = 0.796 ).The MR arthrographic classification showed correlation with the arthroscopic classification of SLAP lesions were 83.1% (49/59)and 79.7% (47/59) for two observers, respectively.Conclusion Shoulder MR arthrography is a reliable method for evaluating SLAP lesions.