Rotator cuff injuries and treatment

Musculoskeletal disorders are among the primary disabling conditions in the United States. After low back and neck pain, the shoulder is the most common area of musculoskeletal pain affecting the general Western population [1]. The incidence of rotator cuff disorders has been reported to range anywhere from 39% to 60% in cadaveric specimens [2], with the supraspinatus tendon having the greatest incidence of pathologic involvement [3]. The shoulder is a unique joint because it allows for significant motion in all planes of direction. This motion is necessary for the hand and upper extremity to reach the functional positions required for activities of daily living, as well as for more strenuous occupational or athletic activities. To accommodate this range of motion, the shoulder is a relatively unconstrained joint that depends on soft-tissue structures for stability and function. Damage to these soft-tissue structures leads to an array of shoulder complaints that are often difficult to elucidate. Shoulder pain is second only to knee complaints as the most common musculoskeletal problem for which patients seek orthopedic care from primary physicians [4]. Despite the relatively high incidence of musculoskeletal disorders affecting the shoulder, the etiologic factors behind rotator cuff pathology is still very much in debate. Before examining the current controversies and theoretical explanations behind the etiologic basis for rotator cuff involvement, however, it is important that we are first able to understand the pertinent anatomy and the general biomechanics of the shoulder joint, and its stabilizing rotator cuff.