Injuries to the AC joint are common and typically occur after a hard fall or direct blow to the top of the shoulder. Depending on the force applied to the shoulder, the fall can cause varying degrees of injury to the AC joint. Low energy impact may result in a mild sprain, while a more forceful injury can cause a complete shoulder separation. An AC joint injury is classified by multiple grades, spanning from a mild sprain (Grade 1) up to complete disruption of the stabilizing ligaments and total AC joint separation resulting in deformity over the top of the shoulder (Grades 3-6).

The main symptom is pain over the AC joint which can be accompanied by a bump on top of the shoulder, depending on the severity of the ligament disruption. AC joint pain ranges from mild tenderness to sharp, intense pain following injury. The pain is commonly felt at the top of the shoulder. Milder grade injuries usually demonstrate improvement of pain and recovery of shoulder function without surgery, even if the bump remains.

An office visit for a suspected AC joint injury will include imaging, a detailed history, and a comprehensive physical examination of the shoulder to confirm a diagnosis and grading of an AC joint injury. X-rays can reveal displacement of the clavicle and help rule out additional bony injuries, such as a clavicle fracture. Additionally, an MRI scan may be performed to evaluate involvement of surrounding ligaments in order to develop an effective and individualized treatment plan.

Not all AC joint injuries are created equal. Treatment is largely based on pain and functional limitations. Injury grade is an important factor to help determine which treatment option is best. Treatment options can include conservative treatment with physical therapy and home exercise, but more significant injuries may be best treated with surgical intervention. Treatment options should be specific to each patient’s needs.

Yes, non-operative management is preferred in most cases. Grade 1-3 AC joint injuries are commonly treated with conservative measures including an initial period of rest with a sling or similar device, medications for inflammation and pain control, and a formal physical therapy program with a well-trained physical therapist. The combination of these non-surgical measures helps decrease pain and usually patients can return to normal activities within 6 weeks.