Recurrent superior labral anterior-to-posterior tears after surgery: Detection and grading with CT arthrography

Purpose: To retrospectively evaluate the sensitivity and specificity of multidetector computed tomographic (CT) arthrography for the detection of recurrent superior labral anterior-toposterior (SLAP) tears in the shoulder of patients who have previously undergone shoulder surgery and are clinically suspected of having a recurrent tear. Materials and Methods: The hospital ethics board did not require patient approval or informed consent for this retrospective review of case records. Multidetector CT arthrograms of 45 shoulders of 45 patients (35 men, 10 women; mean age, 29 years; age range, 21-38 years) who had undergone conventional arthroscopy within 30 days after the CT arthrographic examination were reviewed. Owing to the referral patterns at the authors' institution, all patients were professional athletes. Volumetric multidetector CT arthrography was performed by using a 16-detector CT scanner after the intraarticular injection of iodinated contrast material. All images were independently reviewed by two experienced musculoskeletal radiologists, with disagreements resolved by a third experienced musculoskeletal radiologist. The sensitivity and specificity of multidetector CT arthrography in the detection of any Snyder type II-IV tear was evaluated by using arthroscopy as the reference standard. The numbers and percentages of tears that were assigned the correct Snyder classification with multidetector CT arthrography were reported. Interobserver agreement regarding the correct Snyder classification with multidetector CT arthrography was determined by using κ statistics. Results: With multidetector CT arthrography, recurrent SLAP tears were correctly identified in 35 of 37 patients (95% sensitivity), and the absence of these tears was correctly noted in seven of eight patients (88% specificity). Multidetector CT arthrography- and arthroscopy-derived tear grades were in agreement in 30 (81%) of 37 patients with recurrent SLAP tears. Interobserver agreement at multidetector CT arthrography was substantial (κ = 0.76). Conclusion: In the described highly selected patient population, multidetector CT arthrography was useful for evaluating recurrent SLAP tears.