Sternoclavicular joint dislocations are rare, with anterior types being most common. Posterior (or retrosternal) dislocations are usually secondary to a direct blow to the posterolateral shoulder and are associated with higher morbidity and fatal complications. They can effect structures in the thoracic outlet and anterior mediastinum causing damage to the trachea, great vessels and nerves (brachial plexus, recurrent laryngeal). Posterior dislocations are typically reduced in the operating room.
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