Preoperative Imaging of Anterior Shoulder Instability: Diagnostic Effectiveness of MDCT Arthrography and Comparison With MR Arthrography and Arthroscopy

• Acid Souad
• Le Corroller Thomas
• Aswad Richard
• Pauly Vanessa
• Champsaur Pierre

OBJECTIVE. The purpose of this article is to assess the diagnostic effectiveness of MDCT arthrography in the preoperative planning of anterior shoulder instability compared with MR arthrography and arthroscopy. SUBJECTS AND METHODS. Shoulder MDCT arthrography and MR arthrography examinations prospectively performed in 40 consecutive patients (30 male and 10 female patients; mean age, 26 years) were independently evaluated by two musculoskeletal radiologists who were blinded to the arthroscopic findings, which represented the reference standard. Sensitivity, specificity, and agreement with arthroscopy were determined for osseous, cartilage, and labroligamentous injuries. RESULTS. In detecting glenoid rim fractures, MDCT arthrography had a sensitivity of 100% (12/12), a specificity of 96% (27/28), and better agreement with surgery (kappa = 0.94) than did MR arthrography (kappa = 0.74). For the depiction of glenoid cartilage lesions, MDCT arthrography had a sensitivity of 82% (18/22), a specificity of 89% (16/18), and slightly better agreement with surgery (kappa = 0.70) than did MR arthrography (kappa = 0.66). In identifying anterior labral periosteal sleeve avulsion lesions, MDCT arthrography had a sensitivity of 93% (26/28), a specificity of 100% (12/12), and better agreement with surgery (kappa = 0.89) than did MR arthrography (kappa = 0.74). For the diagnosis of humeral avulsion of the inferior glenohumeral ligament lesions, MDCT arthrography had a sensitivity and a specificity of 100% (2/2) and better agreement with surgery (kappa = 1) than did MR arthrography (kappa = 0.79). CONCLUSION. MDCT arthrography showed better accuracy than did MR arthrography in the detection of osseous, cartilage, and labroligamentous injuries related to anterior shoulder instability. Because MDCT arthrography was particularly reliable for the detection of glenoid rim fractures and humeral avulsion of the inferior glenohumeral ligament lesions, which represent crucial findings in the preoperative planning, this technique may beneficially affect treatment by means of selecting the proper surgical treatment.