AC Separation Causes, Symptoms & Treatment Options

The acromioclavicular joint (AC joint) is formed where the clavicle (collarbone) meets the acromion (the bony point on the top of the shoulder blade). The AC joint is stabilized by a joint capsule as well as two coracoclavicular ligaments (the conoid and the trapezoid). When these structures are injured, usually as a result of a direct blow to the shoulder, this results in an AC separation. Depending on the degree of the damage to the ligaments, the separation may be mild or severe — this is commonly referred to as the degree of AC separation.

An AC separation can occur in six different degrees:

• Type I: The AC ligament is sprained or slightly torn, but still intact. The joint may be slightly out of place. This is the most common type of AC separation.
• Type II: The AC ligament is torn completely through, but the coracoclavicular ligaments are unharmed.
• Type III: The AC joint is completely separated. The AC ligament and the coracoclavicular ligaments are completely torn through. The clavicle may be visibly pushed up or elevated.
• Type IV-VI: AC separations types four through six are rarer and are considered to be more serious injuries.

AC separations are usually the result of traumatic events, like falling on the shoulder or falling on an outstretched arm.

AC separations are common in these sports:

• Cycling
• Football
• Hockey
• Volleyball

Symptoms and the severity of symptoms of AC separations will vary depending on the grade of separation. If you have an AC separation, you may experience one or more of the following symptoms:

• Tenderness and pain when touching the joint
• A bump on the top of the shoulder where the clavicle ends
• Swelling in the shoulder

If you have experienced a traumatic fall and are experiencing symptoms of an AC separation, make an appointment to see an orthopedic specialist. During your appointment, your doctor will examine the affected shoulder, looking for signs of an AC separation.

In order to make a diagnosis, your doctor may prescribe the following imaging tests:

• X-ray

Lower grade AC separations (type I – III), are almost always treated using non-operative treatments. Non-operative treatments for AC separations include:

• Placing the arm in a sling to limit movement and rest the shoulder
• Icing the area to reduce swelling and therefore pain
• Anti-inflammatory medications to reduce swelling
• Physical therapy to restore range of motion and strength

Once the pain and swelling resolve, an exercise program is recommended to rehabilitate the shoulder.

Try these exercises to help address your condition:

Below is a PDF of the Exercise Program

AC Separation

If you experience a higher grade AC separation (Type III-VI), or if your injury is not improving with non-operative treatments, you may require surgery. The goal of surgical treatment for AC separations is to carefully place the joint back into its original position and, if necessary, repair torn ligaments. This surgery is often done through an open incision and often requires a graft to reconstruct the torn ligaments. Occasionally it can be done arthroscopically.

The time it takes you to recover from an AC separation will depend on the grade of the separation, as well as the treatment options that are most effective in your recovery. Type I AC separations, treated nonoperatively, can heal in one to two weeks, while type II tears may take two to four weeks.

If you require surgery, immobilization is often needed for the first 6 weeks after surgery, after which physical therapy is often needed. Usually recovery and return to sports takes at least six months.