IMAGING OF ROTATOR CUFF-IS ULTRASONOGRAPHY RELIABLE?

Abstract

The use of high resolution ultrasonography for the detection of rotator cuff tears has achieved only limited acceptance by orthopaedic surgeons. Uncertainty about the accuracy of ultrasonography may be a contributing factor. The purpose of this study was to evaluate the accuracy of high-resolution ultrasonography compared to shoulder arthroscopy in the detection of rotator cuff tears. 100 consecutive patients with shoulder pain in whom arthroscopic surgery was planned underwent standardized preoperative ultrasonography. The ultrasound examinations were done by a single experienced musculoskeletal radiologist using a standard protocol. The findings at ultrasound were classified into intact cuff, tendinopathy, partial-thickness tear, and full-thickness rotator cuff tears. The size of the tear was measured in centimetres. The location was designated as subscapularis, supraspinatus, infraspinatus, or a combination. All of the subsequent shoulder arthroscopies were done by a single surgeon. The presence or absence of a rotator cuff tear and the size and extent of the tear when present were recorded. We then compared the ultrasonographic findings with the definitive operative findings. For the detection of rotator cuff tears, ultrasound had a sensitivity of 95% and a specificity of 94%; accuracy 95%. There was 100% sensitivity for full thickness tears (specificity 91% and accuracy 95%), while for partial-thickness tears there was a sensitivity of 80%, (specificity 98% and accuracy 95%). In experienced hands, ultrasound is a highly accurate diagnostic method for detecting rotator cuff tears. The results of this study compare favourably with the published results of magnetic resonance imaging for the investigation of this condition. Furthermore, dynamic imaging and comparison with the opposite shoulder is possible with ultrasonography.