Objective To investigate the sensitivity

specificity and accuracy of ultrasound in diagnosing rotator cuff tear. Methods A total of 80 patients with suspected rotator cuff tears admitted to a hospital in Henan Province from September 2018 to January 2021 were selected as subjects. All patients received shoulder ultrasound scans

and the sensitivity

specificity

and accuracy of ultrasound diagnosis of rotator cuff tears were calculated using long-term follow-up（≥6 months） or arthroscopic findings. The receiver operating characteristic（ROC） curves were established to analyze the efficacy of ultrasound diagnosis of rotator cuff tears and the ultrasound characteristics of patients with this condition. Results Among 80 patients suspected of rotator cuff tears

53 cases of rotator cuff tears were confirmed by long-term follow-up or shoulder arthroscopy

and 42 true-positive and 23 true-negative cases were detected by ultrasound among 53 patients with rotator cuff tears. The accuracy rate of ultrasound diagnosis of rotator cuff tears was 81.25%（65/80）

sensitivity 79.25%（42/53）

and specificity 85.19%（23/27）. The ROC curve showed that the area under the curve（AUC） was 0.813. The differences were statistically significant between patients with rotator cuff tears and those without it in the incidence of abnormal intratendon echo（52.83% vs. 7.41%）

the incidence of acromion impingement syndrome（33.96% vs. 7.41%）

and the incidence of synovial bursa effusion（37.74% vs. 70.37%）（P<0.05）. Conclusion Ultrasound demonstrates high diagnostic value for rotator cuff tears

and the clinical application of ultrasound scanning can provide detailed observation of the subscapularis tendon and other parts of the body

and provide a reference basis for the diagnosis of rotator cuff tears by intratendon echogenic features. These benefits justify a wider application of this technique clinically.