Imaging for Anterior Chest Wall Injury After Motor Vehicle Accident
Order a standard posteroanterior (PA) chest radiograph first—or an anteroposterior (AP) portable view if the patient cannot stand—to screen for life-threatening complications like pneumothorax, hemothorax, and pulmonary contusion that directly impact mortality. 1, 2
Initial Imaging Strategy
- Start with a single PA chest X-ray (or AP portable if unstable) as your first-line imaging for all suspected anterior chest wall fractures, including ribs, costal cartilage, and sternum 1, 2
- This approach is recommended by the American College of Radiology across all trauma scenarios because detecting complications matters more than counting every fracture 1, 2
- Chest X-ray will miss approximately 50% of rib fractures, but this does not alter management or outcomes in uncomplicated cases 1, 2
Do NOT Order These Initial Studies
- Avoid dedicated rib series radiographs—they add clinically significant information in only 0.23% of cases, prolong turnaround time, and negatively impact care 1, 2
- Do not order ultrasound as initial imaging despite its ability to detect occult fractures, because it takes 13+ minutes, causes patient discomfort, and rarely changes management 1, 2
- Skip bone scans entirely in acute trauma—they cannot distinguish acute from chronic fractures and remain positive for up to 3 years 1, 2
When to Escalate to CT Chest
Order Contrast-Enhanced CT Chest if:
- High-energy mechanism (motor vehicle collision >35 mph, rollover, ejection) with clinical suspicion for intrathoracic or intra-abdominal injury 1, 2
- Abnormal initial chest X-ray showing mediastinal widening, multiple fractures, or parenchymal abnormality 1
- Hemodynamic instability or signs of ongoing blood loss 2
- First rib fracture (suggests major vascular injury) 1, 2
Order Non-Contrast CT Chest if:
- Multiple rib fractures (≥6 fractures) requiring precise anatomic definition for surgical planning 1, 2
- Bilateral fractures, ≥3 severely displaced fractures, or suspected flail chest 1, 2
- Suspected sternal fracture requiring detailed evaluation 2, 3
Do NOT Order CT if:
- Low-energy mechanism with normal physical exam and stable vital signs 1
- Isolated anterior chest wall tenderness without respiratory distress 1, 2
Critical Risk Stratification
Age ≥65 years with multiple rib fractures requires ICU admission because mortality and morbidity increase dramatically with age and fracture number 1, 2. The following features also mandate ICU-level care:
- Six or more fractured ribs 1, 2
- Three or more severely displaced fractures 1, 2
- Bilateral fractures or first rib fracture 1, 2
- Flail chest (clinical or radiographic) 1, 4
Special Considerations for Anterior Chest Wall
- Costal cartilage fractures are commonly missed on X-ray and require CT for diagnosis—these occur frequently in high-energy blunt trauma but have unclear long-term significance 5
- Sternal fractures warrant heightened suspicion for cardiac contusion or mediastinal injury and may require contrast-enhanced CT 3, 4
- Costochondral junction injuries are best evaluated with point-of-care ultrasound if CT is not indicated 1, 2
Key Clinical Pitfalls to Avoid
- Never assume a normal chest X-ray excludes significant injury—fractures visible on radiography are associated with 3.8-fold increased pulmonary morbidity compared to CT-only detected fractures 1, 2
- Do not rely on absence of rib fractures to rule out solid organ injury—67% of patients with lower rib fractures have associated abdominal injuries even with normal physical exam 2
- Lower your threshold for advanced imaging in elderly patients—they have poor cardiopulmonary reserve and higher complication rates with fewer fractures 1, 2
- Remember that the complications (pneumothorax, hemothorax, pulmonary contusion) carry greater clinical significance than the fractures themselves 1, 4