Fig. 1.

Structure–function relationship of the rotator cuff complex. The supraspinatus muscle-tendon is primarily involved in arm abduction, whereas the subscapularis muscle-tendon predominantly is involved in arm adduction and inward rotation. The infraspinatus and teres minor muscle-tendon are primarily involved in arm outward rotation. Bones, tendons, and muscles are colored yellow, blue, and red, respectively. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)