4 Signs that You May Have an AC Joint Separation — and How to Seek Treatment

ac joint separation

Sudden pain in your shoulder? You may be experiencing the symptoms of an AC joint separation. We’ll help you recognize the signs and seek the best treatment for your condition.

The acromioclavicular joint, or AC joint, is a cartilaginous junction that joins the shoulder blade and the collarbone. Primarily responsible for overhead motions such as throwing, this essential joint can be sprained or separated as a result of direct trauma, often while playing contact sports such as football or hockey.

Like many sprains and strains, an AC joint separation can prevent the shoulder from properly functioning and keep you from engaging in some physical activity. This injury requires a specific course of treatment to ensure that the joint heals as it should. If you think you might have recently separated your AC joint, keep an eye out for the symptoms below.

1. Pain

Like most orthopedic injuries, pain is usually the most prominent symptom of an AC joint separation, with the great majority of patients reporting moderate to severe pain in the afflicted arm or shoulder. The pain is often accompanied by significant swelling, and it tends to worsen when sleeping or lifting the arm.

2. Instability

An AC joint separation can also leave the shoulder with a general feeling of weakness and instability, not unlike the feeling of a pinched nerve. Most patients can’t bear as much weight as they normally can, and others may struggle to use the affected arm at all.

3. Difficulty Moving

Because of the pain and instability, many patients with AC joint separation experience difficulty moving the arm. This restricted range of motion will be particularly noticeable when attempting to move the arm upward.

4. Popping and Changes in Appearance

An AC joint separation can temporarily change the shoulder’s appearance. Many patients notice a protrusion at the top of the shoulder, while others find that the shoulder seems to hang lower than it normally would. Some patients may also hear a distinct popping noise when trying to lift and move the arm or shoulder.


While an AC joint separation can be painful, the good news is that it is easily treatable. With the appropriate course of treatment, most patients can expect to make a complete recovery sooner rather than later.

Most AC joint separations respond quite well to non-invasive treatments such as rest, icing, and anti-inflammatory medications. Placing the arm in a brace or a sling can also promote healing. After several weeks of rest, patients can embark on a physical therapy program designed to restore the shoulder’s range of motion and rebuild the surrounding muscles.

Recovery timelines for AC joint separations depend on the severity of the condition. A minor separation, for example, may heal completely after a week or two, while moderate sprains usually require four to eight weeks of rest and rehabilitation. Sprains that need to be surgically treated often come with a recovery period of several months. Patients whose jobs involve overhead motions or heavy lifting should exercise particular caution before returning to work.

Since every patient has different needs, the recovery process will look and feel a little different for everyone. If you’re concerned about your shoulder, the team of specialists at New York Bone and Joint can help. Backed by decades of experience in treating shoulder injuries, we can work with you to develop a personalized course of treatment that ensures a quick and complete recovery. Contact us today to set up a consultation.

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