By: Elizabeth Wallace, MD

Broken Ribs? Who cares?

Many trauma victims sustain injuries to their ribs, but these are an afterthought to the initial resuscitation. Providers correctly focus on the ABCs, along with major organ injury or extremity deformity, at the expense of the chest wall itself. While many rib fractures require nothing more than analgesia, certain patterns of rib injury require our focused attention.

Chest Wall Trauma

Among victims sustaining thoracic trauma, approximately 50% will have a chest wall injury – 10% of those are minor, 35% are major, and 5% include a flail chest. These injuries are not always obvious and can be overlooked, which is why it is important to palpate the chest wall in everytrauma case and note any deformity, tenderness or crepitus on physical exam.

Chest wall trauma is important because rib fractures can disturb chest wall integrity and disrupt normal ventilation. Fortunately, most individuals have sufficentl respiratory reserve, and can sustain a chest wall insult without compromising respiratory status.  However, children, the elderly and those with underlying lung disease are at higher risk. The elderly specifically have a higher risk of developing pneumonia as a consequence of rib fracture, leading to higher morbidity/mortality within this population.

Simple Rib Fractures

Rib fractures are the most common chest wall injuries, and are often not dangerous on their own. All bones including ribs have higher elasticity and are less ossified in pediatric patients.  And the presence of rib fractures in a kid suggest a higher force mechanism of trauma than may inferred in adults presenting with rib fracture.  As such, these injuries are associated with a higher incidence of underlying soft tissue and organ injury. In adults, the most commonly broken ribs are ribs 4-9 along their posterior aspect, due to their position and fragility.  Ribs 1-3 are sturdier and  fracture of those bones are associated with a higher risk of other intrathoracic injuries. Ribs 9-11 are associated with more intra-abdominal injuries such as liver and splenic lacerations.  These organic injuries arefour times as likely when the right and left lower ribs are fractured, respectively.

Clinical impression and physical exam are sensitive but not specific in diagnosing rib fractures. A chest x-ray is frequently performed in trauma patients, but it often doesn’t reveal simple rib fractures (50% of single rib fractures are not seen on plain film). The greatest value of the chest x-ray in trauma is to identify significant intrathoracic and mediastinal injuries.  For that reason, an upright AP chest x-ray should be ordered on all trauma patients in whom a thoracic injury is considered. Ultrasound can be used to diagnose simple rib fractures, by using the linear US probe, and placing it longitudinally over areas of thoracic tenderness in the trauma patient. The ‘rib series’ radiographs are impractical in the trauma and inappropriate for identification of rib fractures in trauma patient.  CT scans are the most sensitive study to diagnoseoccult rib fractures. However, thoracic CTs are not routinely performed  unless providers are suspicious  other intrathoracic or intraabdominal pathology. The decision to get a CT should be considered based on the mechanism of injury, findings on chest x-ray, or clinical evidence of multiple rib fractures that might be associated with other organ injury. Diagnosis of simple rib fractures in healthy adult patients will not change early trauma management, so the decision to image the patient should be based on patient age, comorbidities, or suspicion for deep organic injury.

The treatment for rib fractures centers on pain control. The main goal is to treat the patient’s pain so they are able to take effective breaths and adequately aerate and ventilate their lungs to prevent complications such as atelectasis and pneumonia. For this reason, subacute care of rib fractures require the use of an incentive spirometer should also be given to encourage sufficient ventilation. Historically, rib fracture patients might receive chest wall binders, but these have long since fallen out of favor, because while they reduce pain, they also promote hypoventilation (and associated complications).

Patients with 3 or more rib fractures require admissionfor aggressive pulmonary therapy and pain control (and admitted to Level 1 Trauma Centers specifically), even when present without deeper injury. Elderly patients carry a much higher incidence of associated pneumonia, atelectasis, morbidity and mortality, and should therefore be treated much more cautiously. Elderly patients with 6 or more rib fractures should be sent to ICU. Usually rib fractures will heal within 3-6 weeks, but pain medications are usually needed for the first 1-2 weeks. Common complications of rib fractures include hemopneumothorax, atelectasis, pneumonia, post-traumatic neuroma, costochondral separation, and delayed bleeding from displaced rib fractures.

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What about sternal fractures?

Sternal fractures are the result of anterior blunt trauma (the chest hitting a steering wheel in a motor vehicle accident as an example). There was previously an association with aortic rupture and spinal injuries, but the presence of airbags has decreased the incidence  of these serious injuries.

Sternal fractures are diagnosed by a lateral chest x-ray or chest CT. When a sternal fracture is diagnosed, a chest CT should be ordered to rule out any other intrathoracic injuries or mediastinal injuries.

Between one and six percent of thoracic trauma patients have cardiac complications.  An EKG (and possibly a serum troponin) should be obtained to evaluate for blunt cardiac injury. This EKG should be repeated in 6 hours to reevaluate, but if normal, the patient can be safely discharged.

Isolated sternal fractures are usually benign, with a low (<1%) mortality and low intrathoracic morbidity. Further imaging should be ordered based on the mechanism and presence of other injuries. Usually conservative management is appropriate, but some patients will require surgical fixation .

 

Flail Chest Injuries

Flail chest injuries result from 3 or more adjacent rib fractures at 2 points, which allows for a freely moving segment. These are among the most serious chest wall injuries, and are commonly associated with pulmonary contusion. Moreover, the pain can cause splinting, atelectasis, hypoxemia, and decreased cardiac output.

Flail chest is a clinicaldiagnosis, though patients receiving mechanical ventilation may have splinting from the positive pressure, making accurate diagnosis challenging.  A CT chest should be done whenever flail is suspected.

There is no firm consensus on treatment for flail.  Previous recommendations included placing the patient with the injured side down/dependent, but this practice has fallen out of favor due to complications of insufficient respiration and attelectasis.  The cornerstone of treatment for flail is aggressive pain control, pulmonary toilet, and close monitoring. Intubation is indicated for any flail patient when respiratory decompensation is evident (being sure to first correct concomitant hemo- or pneumothorax).. Noninvasive positive pressure ventilation (such as BiPAP or CPAP) can be used in an attempt to avoid intubating. Some flail patients may require operative internal fixation, a decision to be made in conjunction with the trauma surgeons.

Treat any patient with flail chest as if a pulmonary contusion exists. These patients carry a 8-35% mortality, directly related to the presence of underlying injuries. Patients may also develop long-term disability later on (dyspnea, chronic thoracic pain, exercise intolerance).

 

Summary Points

   Rib fracture position can indicate associated injuries

Rib fracture carry significant morbidity and mortality in select populations – kids, the elderly, and those with significant lung disease.

   Imaging: based on mechanism, either x-ray or CT – CT most sensitive for other intrathoracic and intraabdominal injuries  (NO rib series)

   Sternal fracture: ECG on arrival and repeat in 6 hours

   Flail chest has high morbidity and mortality

Treatment should focus on pain control and aggressive pulmonary therapy

 

References:

Marx et al. Rosen’s Emergency Medicine: Concepts and Clinical Practice, 7th Edition, Chapter 42: Thoracic Trauma. (387-413). Mosby Elsevier (2010).

Tintinelli et al. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 6th Edition, Section 22: Trauma – Thoracic Trauma. (pp 1595-1613). McGraw-Hill (2004).

FOAMCAST Episode 36: Rib and Sternal Fractures (10/21/2015)

 

Author: Elizabeth Wallace, MD

Faculty Review: Dr. Jordan Spector, MD