summary Sternoclavicular Dislocations are uncommon injuries to the chest that consist of traumatic or atraumatic dislocations of the sternoclavicular joint. Diagnosis can be made with plain serendipity radiographic views. CT studies are generally required to assess for direction of displacement. Treatment is generally observation of atraumatic or chronic anterior dislocations. Closed versus open reduction is indicated for acute dislocations. Etiology Pathophysiology traumatic dislocation direction anterior (more common) posterior (mediastinal structures at risk) important to distinguish from medial clavicle physeal fracture (physis doesn't fuse until age 20-25) mechanism usually high energy injury (MVA, contact sports) atraumatic subluxation occurs with overhead elevation of the arm affected patients are younger many demonstrate signs of generalized ligamentous laxity subluxation usually reduces with lowering the arm treatment is reassurance and local symptomatic treatment Anatomy Medial clavicle first bone to ossify and last physis to close (age 20-25) Sternoclavicular joint osteology diarthrodial saddle joint incongruous (~50% contact) fibrocartilage stability stability depends on ligamentous structures posterior capsular ligament most important structure for anterior-posterior stability anterior sternoclavicular ligament primary restraint to superior displacement of medial clavicle costoclavicular (rhomboid) ligament anterior fasciculus resists superior rotation and lateral displacement posterior fasciculus resists inferior rotation and medial displacement intra-articular disk ligament prevents medial displacement of clavicle secondary restraint to superior clavicle displacement Presentation Symptoms anterior dislocation deformity with palpable bump posterior dislocations dyspnea or dysphagia tachypnea and stridor worse when supine Physical exam palpation prominence that increases with arm abduction and elevation ROM and instability decreased arm ROM neurovascular parasthesias in affected upper extremity venous congestion or diminished pulse when compared with contralateral side provocative maneuvers turning head to affected side may relieve pain Imaging Radiographs recommended views AP and serendipity views findings difficult to visualize on AP serendipity views ( beam at 40 cephalic tilt) anterior dislocation affected clavicle above contralateral clavicle posterior dislocation affected clavicle below contralateral clavicle CT scan study of choice axial views can visualize mediastinal structures and injuries can differentiate from physeal fractures Treatment Nonoperative reassurance and local symptomatic treatment indications atraumatic subluxation chronic anterior dislocation that is minimally symptomatic (> 3 weeks old) technique sling for comfort return to unrestricted activity by 3 months Operative closed reduction under general anesthesia +/- thoracic surgery back-up indications acute anterior dislocations (< 3weeks old) acute posterior dislocations (< 3weeks old) if reduction stable velpeau bandage for 6 weeks may need plaster jacket or figure of eight bandage to distract shoulder elbow exercises at 3 weeks return to sports at 3 months if reduction unstable accept deformity or open reduction and soft-tissue reconstruction open reduction and soft-tissue reconstruction +/- thoracic surgery back-up indications acute posterior dislocation with failed closed reduction dysphagia shortness of breath decreased peripheral pulses chronic anterior or posterior dislocation that remains persistently symptomatic presense of cardiothoracic (CT) surgery is controversial recent studies state that the recommendation for routine involvement of thoracic surgeons in all cases may not be necessary medial clavicle excision indications outdated procedure rarely performed Techniques Closed reduction under general anesthesia reduction technique place patient supine with arm at edge of table and prep entire chest abduct and extend arm while applying axial traction and direct pressure simultaneously apply direct posterior pressure over medial clavicle manipulate medial clavicle with towel clip or fingers Open reduction and soft-tissue reconstruction approach curvilinear incision overlying medial 1/4th of clavicle, SC joint and top of manubirum care to not disrupt the SCM tendon sheath clean incision through the SCJ capsule to allow for repair at the end technique figure of 8 tendon reconstruction using 2 drill holes in the manibrium and 2 in the medial distal clavicle holes should be 1 cm apart to avoid cortical fracture gracilis or semitendinosus allograft/autograft most commonly used Medial clavicle excision approach incision made over medial clavicle resection costoclavicular ligaments must be preserved preserve by resecting < 15mm of medial clavicle repair if injured Complications Cosmetic deformity