Which rotator cuff muscle is most commonly injured?

Which rotator cuff muscle is most commonly injured?

• A. Infraspinatus
• B. Subscapularis
• C. Supraspinatus
• D. Teres Major

Answer: (C)

The muscle most commonly injured is the supraspinatus. Its tendon travels under the acromion and is especially prone to impingement as the arm is raised. Because it initiates the first phase of arm abduction, it bears significant stress during overhead activities and with aging, leading to degenerative tears or acute injuries. This combination makes tears of the supraspinatus the most frequent rotator cuff pathology. The other muscles listed play important roles in shoulder rotation and stabilization, but their injuries are less common. Subscapularis lies on the anterior surface and is less often torn; infraspinatus and teres minor tears do occur but not as frequently as supraspinatus. Teres major is not part of the rotator cuff. Clinically, supraspinatus injuries present with lateral shoulder pain and weakness during initiation of abduction, often with a characteristic painful arc.

The muscle most commonly injured is the supraspinatus. Its tendon travels under the acromion and is especially prone to impingement as the arm is raised. Because it initiates the first phase of arm abduction, it bears significant stress during overhead activities and with aging, leading to degenerative tears or acute injuries. This combination makes tears of the supraspinatus the most frequent rotator cuff pathology.

The other muscles listed play important roles in shoulder rotation and stabilization, but their injuries are less common. Subscapularis lies on the anterior surface and is less often torn; infraspinatus and teres minor tears do occur but not as frequently as supraspinatus. Teres major is not part of the rotator cuff. Clinically, supraspinatus injuries present with lateral shoulder pain and weakness during initiation of abduction, often with a characteristic painful arc.