AC Joint Arthritis
The AC joint is the acromioclavicular joint. It is the joint where the collarbone (clavicle) connects to the shoulder blade (scapula). Over time, this joint can become inflamed or arthritic. Symptoms of AC joint problems include anterior shoulder pain that is worse when bringing the arm across the body. Nonoperative treatment consists of activity modification, anti-inflammatory medications, or a steroid injection into the AC joint. If these measures fail, arthroscopic removal of the distal 1 cm of the collarbone leads to predictable relief of pain.