A 59 yo M presents to the ED complaining of chest pain following an MVC where he was a restrained driver. He reports that he crashed into a cement wall and his chest hit the steering wheel upon impact. On exam, there is noted exquisite tenderness to palpation with a deformity over the sternum. A CXR is obtained. What's the diagnosis? (scroll down for answer)

Diagnosis: Depressed sternal fracture

• Usually from blunt chest trauma/deceleration injuries
• Most common symptom is chest wall pain. Physical exam may reveal bruising, visible chest wall deformity, crepitus w/ palpation
• Mortality is <1%;  however, 2/3 of sternal fractures occur with another injury with associated mortality between 25-45% !
• Examples of concomitant injuries:
• rib fractures, pneumo/hemothorax, cardiac or pulmonary contusion, pericaridal effusion (with risk for tamponade), diaphragmatic injury, thoracic spine fractures
• Gold standard for diagnosis is lateral CXR. CT may miss transverse fractures, but is useful for diagnsois of associated injuires
• Workup:
• ATLS protocol/continous pulse ox
• EKG to evaluate for signs of myocardial contusion (tachycarida, arrhythmias, conduction disturbances, ST elevations/depressions)
• Serial troponins to evaluate for myocardial injury
• Echocardiogram to evaluate for pericardial effusion or for signs of cardiac contusion (wall motion abnormalities, ventricular enlargement, septum rupture, intracardiac thrombus)
• Treatment:
• Patients with nondisplaced isolated sternal fractures with normal EKG/troponin can be discharged home with analgesia and outpatient follow up
• Displaced/unstable fractures may require operative fixation/ICU admission

References: 
Khoriati, Al-Achraf, et al. “Sternal Fractures and Their Management.” Journal of Emergencies, Trauma, and Shock, vol. 6, no. 2, Apr. 2013, pp. 113–116. doi:10.4103/0974-2700.110763.