Shoulder pain is a common complaint by patients, and it can be due to a variety of causes. The major cause of shoulder pain in patients older than 40 years is rotator cuff impingement and tears. With the development of new arthroscopic techniques for treating rotator cuff disorders, magnetic resonance imaging (MRI) has played an increasingly important role as a noninvasive test for determining which patients may benefit from surgery.
Rotator Cuff Anatomy:
The rotator cuff consists of the supraspinatus, infraspinatus, subscapularis, and teres minor muscles and tendons. At the distal aspect of the rotator cuff, the supraspinatus and infraspinatus tendons splay out and interdigitate, forming a common continuous insertion on the middle facet of the humeral greater tuberosity. To a lesser extent, the supraspinatus and subscapularis tendons demonstrate contiguity, with interwoven fibers from these two tendons enveloping the biceps tendon. The rotator cuff is a functional-anatomic unit rather than four unrelated tendons, and injury to one component may have an influence on other regions of the rotator cuff.