44 year old male patient came with painfull arc of shoulder movement, T1 weighted oblique coronal image shows hyperintense abnormal signal seen in the supraspinatous tendon (arrow).
Supraspinatus tendonitis is often associated with shoulder impingement syndrome. The common belief is that impingement of the supraspinatus tendon leads to supraspinatus tendonitis (inflammation of the supraspinatus/rotator cuff tendon and/or the contiguous peritendinous soft tissues), which is a known stage of shoulder impingement syndrome.
It is basically chronic degenerative tendinitis leading to some degree of mucoid degeneration seen on MRI as increased signal intensity without altered rotatory cuff contour. Increased signal intensity appreciated on T1 and PD weighted images.