Surgeon-Operated In-Office Ultrasonography for the Diagnosis of Rotator Cuff Tears: A Comparison with Magnetic Resonance Imaging

Objective: Few investigators have evaluated whether ultrasonography operated by a surgeon during a patient’s clinic visit is capable of obtaining a similar degree of accuracy as magnetic resonance imaging in regard to the diagnosis of rotator cuff tears and lesions of the biceps tendon. The purpose of this study was to clarify the accuracy of in-office ultrasonography for the diagnosis of rotator cuff tears in comparison to magnetic resonance imaging. Methods: One hundred and three patients (105 shoulders) with a clinical diagnosis of impingement and suspected rotator cuff tear, who subsequently underwent arthroscopic surgery were retrospectively enrolled in this study, including 7 males with 89 shoulders, and 33 females with 33 shoulders, and their mean age was 60.9 years (range, 30 to 83 years). The subjects were examined using ultrasonography and magnetic resonance imaging within three months pre-operatively per normal practice of the outpatient clinic. The two modalities were then compared to the reference standard, arthroscopic findings. Results: Intra-operatively, 79 full-thickness and 15 partial-thickness rotator cuff tears were found. The agreement between ultrasonography and magnetic resonance imaging for diagnosis of rotator cuff tears was statistically good; observed degree of agreement was 87% with Kappa coefficient of 0.73. Ultrasonography showed a sensitivity of 94% and a specificity of 100% for full-thickness tears, and a sensitivity of 80% and a specificity of 91% for partial-thickness tears. The agreement of the two modalities for diagnosis of lesions of the biceps tendon was also good; observed degree of agreement was 93% with Kappa coefficient of 0.76. In addition, ultrasonography showed comparable accuracy for classifying the size of rotator cuff tears to that of magnetic resonance imaging. Conclusion: Surgeon-operated in-office ultrasonography is an appropriate technique for the assessment of rotator cuff tears with a comparable sensitivity and specificity to that of magnetic resonance imaging.