(a) The structure of the rotator cuff consists of four muscles that all play a role in the motion of the rotator cuff. The four muscles that are responsible for this motion are: the Supraspinatus muscle, the Infraspinatus muscle, the Teres Minor muscle, and the Subscapularis muscle. Each of these muscles originate from the scapula and attach into the humerus. The Supraspinatus muscle originates in the Supraspinatus Fossa and attaches to the greater tubercle of the humerus. The infraspinatus originates in the Infraspinatus Fossa and like the Supraspinatus muscle, attaches to the greater tubercle of the humerus. The Teres Minor muscle originates in the lateral scapulae border and attaches to the greater tubercle of the humerus. The Subscapularis
