Ultrasonography and arthrography in the diagnosis of tears of the rotator cuff.

The accuracy of ultrasonography and arthrography in the prediction of lesions of the rotator cuff was evaluated and compared with the operative findings in a retrospective study of forty-nine patients (forty-nine shoulders). In the detection of full-thickness (stage-III) tears of the rotator cuff, ultrasonography had an over-all sensitivity of 74 per cent, a specificity of 95 per cent, an accuracy of 84 per cent, a predictive value of a positive test of 95 per cent, and a predictive value of a negative test of 75 per cent. In contrast, arthrography demonstrated a sensitivity of 93 per cent, a specificity of 95 per cent, an accuracy of 94 per cent, a predictive value of a positive test of 96 per cent, and a predictive value of a negative test of 91 per cent. Ultrasonography could not reliably differentiate between partial (stage-II) and full-thickness (stage-III) tears. Lesions of the long head of the biceps brachii tendon were recorded by ultrasonography for twenty-two patients (45 per cent) and by arthrography for eleven patients (22 per cent). The ultrasonographic finding of fluid in the sheath of this tendon is not a reliable sign of a lesion in the tendon.