ObjectiveTo investigate the value of ultrasound in the diagnosis of partial rotator cuff tears（PRCTs）

and to analyze the significance of different ultrasonic signs on PRCTs.MethodsEighty-one patients were underwent ultrasound and MRI before arthroscopy were enrolled.The arthroscopic results were used as the gold standard to compare the diagnostic efficacy of ultrasound and MRI for PRCTs. Correlation between different ultrasonic signs and PRCTs were analyzed

and the Logistic regression was performed to evaluate the risk factors for PRCTs.Results between ultrasound and MRI in the diagnosis of PRCTs and supraspinatus tendon tear. Hypoechoic or anechoic focus in the tendon

localized thinning of tendon thickness and fluid in the biceps tendon sheath were correlated with PRCTs（Φ =0.353

0.339

0.217

P=0.001

0.002

0.045）.Logistic regression analysis showed that all these three factors can predict PRCTs（OR=8.463

7.658

5.316

P=0.007

0.012

0.047）.Conclusion and out of the tendon should be both considered at diagnosis.