MR findings are consistent with partial interstitial tear of the distal supraspinatus tendon. 

Partial tears of tendons of rotator cuff are more difficult to reliably detect on MR than full thickness tears. It is of greatest importance to recognize them, describe their extensiveness and potential communication with bursal or articular surface. Therefore, for better accuracy direct MR arthrography of the shoulder is advised.   

Interstitial or intrasubstance tears have additional importance since they are not visible on arthroscopy and precedent MRI report could be declared as a false positive.