shoulder

The shoulder is a complex, highly mobile joint where the upper arm (humerus) connects to the shoulder blade (scapula), supported by muscles, tendons, and ligaments. It allows a wide range of movements like lifting, rotating, and reaching. The shoulder's stability comes from the rotator cuff muscles, which hold the humeral head in the shallow socket of the scapula. Because of its extensive mobility, the shoulder can be vulnerable to injuries such as strains, tears, or dislocations, often caused by overuse, trauma, or aging. Proper function requires a balance between mobility and stability for effective movement.