Which muscle is most commonly involved in a rotator cuff tear?

Which muscle is most commonly involved in a rotator cuff tear?

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

Answer: (A)

The muscle most commonly involved in a rotator cuff tear is the supraspinatus. This tendon sits right up under the acromion as the arm is lifted, so it bears the brunt of impingement and repetitive overhead activity. Its role is to initiate arm elevation, which means it undergoes a lot of stress early in the motion. Over time, degenerative changes accumulate, especially in the tendon’s “critical zone” where blood supply is poorer, making tears more likely and healing slower. Because of this, a supraspinatus tear typically presents with pain when lifting the arm overhead, and weakness in the initial portion of abduction. While other rotator cuff muscles (infraspinatus, subscapularis, teres minor) can be involved, they’re less commonly torn as isolated injuries and tend to be affected later or in larger cuff tears, explaining why supraspinatus is the most frequently implicated.

The muscle most commonly involved in a rotator cuff tear is the supraspinatus. This tendon sits right up under the acromion as the arm is lifted, so it bears the brunt of impingement and repetitive overhead activity. Its role is to initiate arm elevation, which means it undergoes a lot of stress early in the motion. Over time, degenerative changes accumulate, especially in the tendon’s “critical zone” where blood supply is poorer, making tears more likely and healing slower.

Because of this, a supraspinatus tear typically presents with pain when lifting the arm overhead, and weakness in the initial portion of abduction. While other rotator cuff muscles (infraspinatus, subscapularis, teres minor) can be involved, they’re less commonly torn as isolated injuries and tend to be affected later or in larger cuff tears, explaining why supraspinatus is the most frequently implicated.