[MR tomography versus CT arthrography in glenohumeral instabilities].

In a prospective study the diagnostic value of MRI compared to CT arthrography (CT-A) was evaluated in 26 patients with 27 instable shoulder joints. Surgical and/or arthroscopic correlation was available in all cases. Both methods showed a high accuracy (96% CT-A, 94% MRI) in the evaluation of the glenoid labrum. CT-A was significantly superior to MRI in the detection of capsular lesions (sensitivity 96% vs. 44%, accuracy 96% vs. 72%, negative predictive value 96% vs. 67%). CT-A and MRI results regarding humeral head fractures were similar; fractures of the glenoid rim were better detected by CT-A, the difference, however, was statistically not significant. Overall, CT-A proved to be superior to MRI, as lesions of the joint capsule were shown with greater certainty.