What to Know About a Separated Shoulder (AC Joint Injury)
The acromioclavicular (AC) joint is located where the clavicle (collarbone) connects with the acromion process of the scapula (shoulder blade) at the top of the shoulder. Like other joints in the human body, the bones of the AC joint are covered with cartilage and the joint has an interior cartilage disk. The joint is reinforced by strong ligaments called the coracoclavicular ligaments. Any of these structures can become damaged, typically during a fall, and lead to a separated shoulder. Van Nuys, Westlake Village, Thousand Oaks and Los Angeles, California orthopedic shoulder specialist, Dr. Mark Getelman is highly trained and experienced at treating AC joint injuries.
An acromioclavicular joint injury is commonly caused by a fall or other trauma to the point of the shoulder joint. An AC joint injury, also known as a “shoulder separation” or “separated shoulder” can lead to a number of injuries, including:
- AC Joint Sprain
- AC Joint Separation
- AC Joint Fracture of the Clavicle or Acromion
- AC Joint Arthritis
A fall or other trauma can lead to a mild sprain or a separated shoulder. In mild injuries, the AC ligaments are simply stretched and these are classified as grade I injuries. In severe injuries, the ligaments can partially tear (grade II) or completely tear (grade III).
Separated Shoulder Symptoms
Symptoms of an AC joint injury or a separated shoulder range from minor swelling and tenderness to severe shoulder pain, depending on the grade of injury. A grade I injury typically causes minor pain, swelling and bruising. A grade II injury commonly causes moderate to severe pain, swelling and perhaps a small visible bump on the top of the shoulder. A grade III injury generally causes severe pain, instability and a visible deformity of the shoulder joint.
Separated Shoulder Diagnosis
A separated shoulder is most often diagnosed by the history of the injury, a thorough physical examination and a series of X-rays. During the examination, Dr. Getelman will examine the injured shoulder for tenderness and bruising in the area of the AC joint. The X-ray findings will be used to confirm the diagnosis.