Shoulder > Shoulder Separation

What is the Acromioclavicular Joint?

The top, or roof, of your shoulder blade is called the acromion. Your collarbone, called the clavicle, connects to the shoulder blade at the acromioclavicular (AC) joint and to your chest bone, called the sternum, at the sternoclavicular (SC) joint. Ligaments attach the bones together to hold the AC joint together. One set of ligaments surrounds the joint to form the joint capsule, and two other sets of ligaments hold the collarbone down by attaching to the bony knob on the top of your shoulder blade, which is called the coracoid process.

A shoulder separation is the common term that describes damage to the ligaments connecting your collarbone and shoulder blade. Shoulder separations generally are classified into six types of severity:

   Type 1 – Mild sprain or stretching in the ligaments around the joint.

   Type 2 – Moderate sprain with some displacement of your collarbone.

   Types 3-6 – Severe sprains with all major ligaments torn. The injured shoulder may be lower than the other shoulder (it may look like the collarbone is raised up but really the shoulder blade is in a lowered position). The type is determined by the location of the displaced collarbone.

Collisions and falls, especially off a bicycle, are the most common causes of separated shoulders. This direct trauma can push your shoulder blade down farther than your collarbone can bend. The ligaments around the AC joint stretch or tear, allowing space for the bones to separate. Contact sports like football and hockey put athletes at the greatest risk, but accidental falls or collisions in any sport can cause a shoulder separation.

Types 1 and 2 separations usually heal with non-operative treatment. Adherence to a rehab program can strengthen the muscles in the shoulder enough to prevent future separations and avoid orthopedic surgery. Treatment of a Type 3 separation is controversial. Some may adequately heal without surgery whereas some may require surgical treatment. Your physician will carefully evaluate your unique physical characteristics and athletic goals to determine whether or not surgery is a good option for you. Types 4-6 most frequently need surgery, but sometimes can be treated by closed reduction (putting the displaced collarbone back in place) and a sling, depending on your activity level and expectations.

There usually are three parts to an orthopedic evaluation: medical history, a physical examination, and tests that your doctor may order.

Your physician likely will ask about your activities, which may have caused your shoulder separation. You will probably be asked when the soreness or pain began. If you have had any prior shoulder injuries, your physician will ask about treatments you have tried in the past. You will probably be asked how long your shoulder took to begin swelling, and whether you were able to continue playing after you noticed the pain. Physicians also typically ask about other conditions, such as arthritis, diabetes, and allergies, and medications currently being taken. You may also be asked about your physical and athletic goals – information that will help your physician decide what treatment might be best for you in achieving those goals.

PHYSICAL EXAM

To diagnose a shoulder separation, physicians usually press areas around the front and back of your shoulder to test for tenderness around the joint. Your physician may hold your arm up at shoulder height and move it inward across your chest to test the stability of the AC (acromioclavicular) joint.

TESTS

X-rays usually are given to help your physician check for fractures and see the position of your collarbone and shoulder blade. You may be asked to hold weights in your hands during the X-rays to slightly stress the AC joint, which provides an image for diagnosing instability.

RELATED TOPIC

   Imaging techniques

To diagnose a shoulder separation, physicians usually press areas around the front and back of your shoulder to test for tenderness around the joint. Your physician may hold your arm up at shoulder height and move it inward across your chest to test the stability of the AC (acromioclavicular) joint.

Tests

X-rays usually are given to help your physician check for fractures and see the position of your collarbone and shoulder blade. You may be asked to hold weights in your hands during the X-rays to slightly stress the AC joint, which provides an image for diagnosing instability.