A sprain of the acromioclavicular (AC) joint is a common injury among athletes, especially those who engage in contact sports such as football, rugby, and hockey. The AC joint is located at the top of the shoulder where the clavicle (collarbone) meets the acromion (part of the shoulder blade). A sprain of the AC joint occurs when the ligaments that hold these bones together are stretched or torn.
Symptoms of a sprain of the AC joint include pain at the top of the shoulder, swelling, and tenderness. The pain may be worse when you move your arm or try to lift something. In severe cases, there may be a visible bump or deformity at the top of the shoulder.
The most common cause of a sprain of the AC joint is a fall onto the shoulder, usually with the arm outstretched. This can happen in a variety of sports and activities, or even in a simple slip-and-fall accident. Other causes may include a direct blow to the shoulder or a sudden twisting motion.
Diagnosis of a sprain of the AC joint typically involves a physical examination, X-rays, and possibly an MRI. Treatment usually involves rest, ice, compression, and elevation (RICE) to reduce swelling and pain. In some cases, a sling or brace may be recommended to immobilize the shoulder and allow the ligaments to heal. Physical therapy exercises may also be prescribed to help restore strength and range of motion to the shoulder.
In most cases, a sprain of the AC joint will heal on its own within a few weeks to a few months. However, in severe cases, surgery may be required to repair or reconstruct the damaged ligaments.
If you suspect that you have a sprain of the AC joint, it is important to seek medical attention as soon as possible to prevent further damage and to start treatment. With proper rest and rehabilitation, most people are able to return to their normal activities within a few weeks to a few months.