Evaluation of chronic tears of the rotator cuff by ultrasound - A new index

The diagnosis of chronic lesions of the rotator cuff is challenging. We hav e developed a new index to improve the sonographic diagnosis of chronic tea rs of the cuff. In a pilot study, we examined 50 asymptomatic healthy volunteers by ultraso und to establish the diameter of the rotator cuff in relation to the tendon of the long head of biceps. Subsequently, the index was calculated in 64 p atients who had had shoulder pain for more than three months caused by clin ically diagnosed lesions of the rotator cuff. The compensatory hypertrophy of the biceps tendon was quantified sonographically in relation to the diam eter of the cuff. Comparison with the contralateral shoulder revealed a significantly higher biceps rotator-cuff ratio (p < 0.05) for patients with torn rotator cuffs. A ratio greater than 0.8 was considered pathological (index positive); the mean ratio in the control group was 0.43. The sensitivity of a positive ind ex was 97.8%, the specificity 63.2%, the positive predictive value 86.3%, a nd the negative predictive value 92.4% in comparison with surgical findings . Use of the index improves sensitivity in the diagnosis of chronic tears of the cuff by ultrasound.