The diagnosis of an AC joint sprain is usually made by observation of symptoms as well as a detailed history and physical exam performed by an orthopaedic surgeon. Diagnostic imaging (X-rays) studies will be obtained to look for fractures or other underlying conditions; the X-rays are also used to document the grade of the sepeartion.
Grade IV, V and VI injuries are relatively uncommon injuries, accounting for approximately 10 percent of all AC Joint separation injuries. These are the most severe grades of injury, and are typically the result of especially traumatic events, such as an automobile accident or a particularly traumatic fall.
A "bump" may be present over the tip of the collarbone.
Symptoms can range from tenderness over the joint to a complete seperation of the AC Joint, with considerable swelling and obvious deformity of the shoulder.
Bluish bruising may appear soon after the injury.
A popping or tearing sensation inside the injured shoulder may occur with movement.
The inability to lift the arm away from the body due to severe pain.