Shoulder Separation (Acromioclavicular Joint Separation)
The acromioclavicular joint – or AC joint, as it’s also known – is a small joint that’s between the collarbone and the shoulder blade. It’s very important for positioning the shoulder and spaced appropriately so it can function to its fullest extent.
One of the more common AC joint injuries is something called an AC joint separation, or a shoulder separation, where the collarbone goes out of alignment with the shoulder blade. This usually happens from a direct fall onto the shoulder and is commonly seen in athletes, especially cyclists who are involved in an accident or when they go over the handlebars. Another common issue that affects the AC joint is AC joint arthritis. This typically comes from repetitive heavy loads and is common in people who have to do a lot of overhead work for their jobs, or in weightlifters.
An AC joint separation typically involves a lot of pain right around the AC joint after some type of injury, like a fall on the shoulder. There could also sometimes be a deformity where the collarbone is sticking up quite a bit above the rest of the shoulder. As far as AC joint arthritis, that typically manifests itself as pain around the AC joint, especially with overhead activity, reaching around the back or reaching across the body.
AC joint injuries are classified based on how much the collarbone is displaced from the rest of the shoulder. It can be graded from grade 1 to 6, with the higher numbers being more severe. Most AC joint injuries that we see are types 1, 2 and 3, and most of those can be treated without surgery. Sometimes in very high-level athletes or people with physically demanding jobs, it is more beneficial to fix a type 3 AC joint separation. This will typically involve surgery and repairing some of the ligaments that provide stability to that joint.
If you think you may have had an AC joint separation or have a lot of pain around your AC joint, I would recommend that you go see someone who specializes in treatment of shoulder conditions, that can appropriately work you up with X-rays and a physical examination to figure out exactly what’s going on with your shoulder.