Presentation
Brought to the Emergency Department by ambulance following a car collision. The patient was cycling downhill at speed and collided with the back of a four wheel drive that had hit the brakes suddenly. A CT trauma series was performed.
Patient Data
- Right 1st and 2nd rib fractures. The right first rib is broken in two positions, anteriorly between the right subclavian artery and vein with moderate displacement and posteriorly with minimal displacement. No contrast extravasation from these vessels to suggest active hemorrhage.
- Left 1st to 6th rib fractures. All these ribs have fractures occurring at two places (indicating a flail segment), one posteriorly with marked displacement and one anteriorly along the rib with minimal displacement.
- A minimally displaced fracture of the manubrium.
- Extensive gas within the mediastinum, root of the great vessels, and within the anterior aspect of the pericardium. There is further gas within the pectoralis major muscle and within the subcutaneous tissue bilaterally.
- Bilateral small hemopneumothoraces.
Case Discussion
Rib fractures are a common traumatic occurrence, where the 4th to 9th ribs are most commonly fractured. Superior rib fractures of the 1st to 3rd ribs are more commonly associated with subclavian vasculature as well as brachial plexus injury. More inferior rib fractures of the 10th to 12th ribs are associated with visceral injury, in particular, the spleen, kidney and liver 5. In general, the greater the number of fractured ribs, the more severe the causative injury.
Rib fractures can have multiple complications. These include:
- Pneumothorax
- Hemothorax
- Pulmonary contusions
- Flail chest
- Pneumonia
- Atelectasis
Sternal fractures are also relatively uncommon, but are typically found in passengers in motor vehicle accidents (60-90%). The passengers have typically worn a restraining belt, however airbags did not deploy. Fractures of this area occur either at the sternum, or at the manubrial body - the xiphoid process doesn't usually fracture.
Sternal trauma is an uncommon occurrence, typically found in patients with blunt chest trauma or deceleration trauma (from motor vehicle accidents)1.
Sternal fracture can be diagnosed with sternal view plain film radiography. Ultrasound has recently been used for patients with suspected sternal fracture, but indeterminate plain films. The sensitivity is claimed to be 100%2.
Isolated sternal fractures have a good prognosis, low mortality and are commonly treated on an outpatient basis3,4. Due to the large amount of force associated with these injuries, concomitant injuries are common and can complicate management. Such concomitant injuries include:
- Soft tissue injuries
- pneumothoraces, hemothoraces, cardiac tamponade, myocardial, pulmonary contusions, abdominal and diaphragmatic injury
- 6-12% of patients with sternal trauma will have an associated myocardial contusion4
- Injuries to the chest wall
- rib fractures, flail chest and sternoclavicular dislocation
- Injuries to the spine, appendages and cranium
Complications from sternal injury include:
- Short term complications - musculoskeletal chest pain requiring analgesia to control. Poorly controlled chest pain can lead to impaired ventilation and pulmonary infection. In this patient, their aspiration pneumonia may be exacerbated by sternal fracture pain.
- Long term complications - non-union, pseudoarthroses
Rare complications include osteomyelitis, sternal abscess formation and mediastinitis.
Management is typically conservative with sternal fractures. For displaced or unstable chest fractures require operative fixation with sternal wires or osteosynthesis.
Case contributed by A/Prof. Pramit Phal.