A positive Drop Arm test indicates pathology in which structure or muscle?

A positive Drop Arm test indicates pathology in which structure or muscle?

• A. Supraspinatus (rotator cuff) tear
• B. Infraspinatus tear
• C. Subscapularis tear
• D. Teres minor tear

Answer: (A)

The Drop Arm test targets the supraspinatus function within the rotator cuff. When the arm is raised to about 90 degrees of abduction, the supraspinatus helps initiate and control that movement, keeping the humeral head centered as the deltoid continues the lift. If the supraspinatus tendon is torn, this stabilizing action is lost, so the deltoid can’t control the descent and the arm drops abruptly from the raised position. A positive result therefore indicates supraspinatus pathology, commonly a rotator cuff tear. Tears of the other rotator cuff muscles affect other motions and don’t produce the same drop sign in the same way.

The Drop Arm test targets the supraspinatus function within the rotator cuff. When the arm is raised to about 90 degrees of abduction, the supraspinatus helps initiate and control that movement, keeping the humeral head centered as the deltoid continues the lift. If the supraspinatus tendon is torn, this stabilizing action is lost, so the deltoid can’t control the descent and the arm drops abruptly from the raised position. A positive result therefore indicates supraspinatus pathology, commonly a rotator cuff tear. Tears of the other rotator cuff muscles affect other motions and don’t produce the same drop sign in the same way.