AC joint

The AC joint, or acromioclavicular joint, is the point where the collarbone (clavicle) meets the highest point of the shoulder blade (acromion). It helps hold the shoulder together and allows for smooth movement of the shoulder blade during arm movements. This joint is stabilized by ligaments and can sometimes be injured or separated due to falls or trauma, causing pain or limited mobility. Understanding its function helps in diagnosing and treating shoulder injuries effectively.