The AC joint is located in the shoulder where the collarbone and shoulder blade meet. The shoulder blade, also known as the scapula, has an area called the acromion where it is joined with the collarbone, or clavicle. As with other joints in the body, the areas where these bones meet have cartilage to reduce friction during movement. Damage to the cartilage or joint can cause AC joint separation.

The Most Common Cause for AC Joint Separation

The ligaments surrounding and stabilizing the AC joint are most often injured in a direct fall on the shoulder. This can happen during sports or an accident. The injury is graded according to certain criteria. The severity of the separation depends on how badly the ligaments are torn and which ones are involved in the tear.

Surgery May Not Be Required

In general, conservative treatment is applied to AC joint separations. Pain is usually relieved by resting the joint, using over-the-counter pain relievers and icing the injured area. Often, full recovery is made within a few weeks.

You may notice some shoulder pain and shoulder or arm weakness. Bruising or swelling in the area of injury is often present, along with a bump at the top of the shoulder. Because the collarbone has separated from the scapula, there is usually limited shoulder movement.

Arthritis Can Develop as a Result

The AC joint can become irritated as a result of repetitive overhead motions. People who participate in certain sports such as baseball or basketball fit into this category. Those who participate in contact sports such as football, wrestling and hockey are at a higher risk for falls or collisions, which can cause AC joint separation. Arthritis can develop when the cartilage is injured. This is one of the complications that can emerge from AC separation.

If you suspect an AC separation or have pain in your shoulder, contact Dr. Steven Struhl. Early intervention can lead to faster healing.

Posted on behalf of Steven Struhl MD