Which of the following is not a rotator cuff muscle?

The correct choice highlights the fact that the suprascapularis is not a recognized rotator cuff muscle. The rotator cuff is comprised of four specific muscles: supraspinatus, infraspinatus, teres minor, and subscapularis. Each of these plays a crucial role in stabilizing the shoulder joint and facilitating its range of motion.

The supraspinatus helps with arm abduction, the infraspinatus and teres minor are instrumental in lateral rotation of the arm, and the subscapularis aids in medial rotation. In this context, the suprascapularis does not belong to this group, which is why it is identified as the exception. Understanding these muscles and their functions is essential in the study of biomechanics, particularly when considering movement patterns and the prevention of shoulder injuries.