summary Scapulothoracic Dissociation is a high-energy traumatic disruption of the scapulothoracic articulation often associated with severe neurovascular injuries, scapula fractures, and clavicular fractures. Diagnosis can be made with the edge of the scapula being displaced > 1 cm from the spinous process as compared to the contralateral side. CT scan of the chest will show an asymmetric distance from the spinous process to the medial edge of the scapular body. Treatment is generally open reduction and internal fixation of associated fractures and urgent exploration in the setting of vascular injuries. Functional outcome is dependent on the level of neurologic injury. Etiology Mechanism usually caused by a lateral traction injury to the shoulder girdle involves significant trauma to heart, chest wall and lungs Associated conditions orthopaedic scapula fractures clavicle fractures AC dislocation/separation sternoclavicular dislocation flail extremity (52%) complete loss of motor and sensory function rendering the extremity non-functional vascular injury subclavian artery most commonly injured axillary artery neurologic injury (up to 90%) ipsilateral brachial plexus injury (often complete) neurologic injuries more common than vascular injuries Anatomy Scapulothoracic joint a sliding joint articulates with ribs 2-7 moves into abduction at 2:1 ratio GH joint 120° ST joint 60° Neurovascular anatomy brachial plexus subclavian artery axillary artery Presentation History history of high energy trauma Symptoms pain in involved upper extremity (UE) numbness/tingling in involved UE Physical exam inspection significant swelling in shoulder region bruising around shoulder vascular exam decreased or absent pulses in involved UE neurological exam neurologic deficits in UE neurological status critical part of exam Imaging Radiographs required views AP chest recommended view AP and lateral of shoulder as tolerated appropriate images of suspected fracture sites findings laterally displaced scapula edge of scapula displaced > 1 cm from spinous process as compared to contralateral side widely displaced clavicle fx AC separation sternoclavicular dislocation CT scan recommended views chest CT axial views findings asymmetric distance from spinous process to medial edge of scapular body Angiogram indicated to detect injury to subclavian and axillary artery Treatment Nonoperative immobilization/supportive care indications patients without significant vascular injury who are hemodynamically stable patients may have adequate collateral flow to UE even with injury Operative high lateral thoracotomy with vascular repair indications axillary artery injury in hemodynamically unstable patient median sternotomy with vascular repair indications more proximal arterial injury (i.e., subclavian artery) in a hemodynamically unstable patient ORIF of the clavicle or AC joint indications associated clavicle and AC injuries forequarter amputation indications complete brachial plexus injury Prognosis Mortality rate of 10% Functional outcome is dependent on neurologic injury if return of neurological function is unlikely, early amputation is recommended