Painful arc syndrome is a shoulder pathology in which the supraspinatus tendon becomes mechanically impinged beneath the acromion process during a specific range of glenohumeral abduction, producing pain that is present only within that arc and absent outside it. This reflects the broader biomechanical principle of shoulder abduction as a sequential, multi-muscle process (initiated by the supraspinatus, continued by the deltoid, and accompanied by scapular rotation via the trapezius and rhomboids), in which impingement of a specific tendon against a bony structure at a defined joint angle range is the mechanism underlying the syndrome.
Painful arc syndrome is a shoulder pathology in which the supraspinatus tendon becomes mechanically impinged beneath the acromion process during a specific range of glenohumeral abduction, producing …