Which group of muscles and tendons is responsible for stabilizing the shoulder joint?

The rotator cuff is a crucial group of muscles and tendons that play a vital role in stabilizing the shoulder joint. This group consists of four muscles: supraspinatus, infraspinatus, teres minor, and subscapularis. Together, they work to keep the head of the humerus securely in the shallow socket of the shoulder blade (scapula) during arm movements. This stability is essential for both the strength and range of motion of the shoulder, as it allows for various actions, such as lifting and throwing.

Other muscle groups listed have different functions. The deltoid muscles primarily focus on the movement of the shoulder and are responsible for raising the arm. While they contribute to shoulder joint movement, they are not primarily responsible for its stabilization. The pectoral muscles mainly assist with movements of the chest and shoulder but do not play a significant role in stabilization. The biceps brachii, while important for flexing the elbow and rotating the forearm, does not contribute directly to the stability of the shoulder joint. Thus, the rotator cuff is the essential structure for maintaining the integrity and stability of the shoulder during various activities.