Comparative study between Dynamic Ultrasonography and MRI in Evaluation of Shoulder Impingement Syndrome

Abstract

Subacromial impingement is the most frequent cause of shoulder pain, accounting for up to 60% of all shoulder complaints .The term shoulder impingement was first introduced by Neer 1972 and referred to compression of rotator cuff, subacromial bursa and biceps tendon against the undersurface of the acromion & coraco-acromial ligament , that exaggerates on elevation of the arm. Recent literatures describe shoulder impingement as a group of symptoms rather than specific diagnosis, in this current opinion; it is thought that numerous underlying pathologies may cause impingement. It is classified into intrinsic and extrinsic impingement. In intrinsic impingement, there is partial or full thickness tear of the rotator cuff tendons as a result of degenerative process that occurs with overuse tension. In extrinsic impingement, there is mechanical compression induced by some structures external to the tendons resulting in tendon inflammation or degeneration.