Anatomy, Shoulder and Upper Limb, Sternoclavicular Joint

The sternoclavicular (SC) joint is a saddle-shaped, synovial joint that is the primary skeletal connection between the axial skeleton and the upper limb. A fracture of the clavicle renders the upper limb virtually useless.  The sternoclavicular joint is one of five articulations essential for the function of the upper limb. Several critical structures have an anatomical relationship to the sternoclavicular joint, including the brachiocephalic arterial trunk, internal jugular vein, and common carotid artery. Other structures include the vagus and phrenic nerves, trachea, and esophagus. Thus, in addition to its critical role in stabilizing and supporting the upper limb, the sternoclavicular joint and its component parts - the clavicle and sternum - play an essential protective role for structures entering the thorax.