The shoulder joint is one of the most mobile joints in the body, allowing for a wide range of movements in various directions. It is a ball-and-socket joint where the ball-shaped head of the humerus (upper arm bone) fits into the shallow socket of the scapula (shoulder blade), known as the glenoid. This joint's mobility makes it essential for many daily activities, including lifting, reaching, and rotating the arm. The shoulder is stabilized by ligaments, tendons, and the rotator cuff muscles, which help maintain the integrity of the joint and enable smooth motion. However, its high range of motion also makes it prone to injuries like rotator cuff tears, shoulder dislocations, and impingement syndrome.