The larynx (voice box) performs many different functions, including breathing and speech. This is why it can be injured during a trauma such as a car accident, assault, or sports injury. The patient may be asymptomatic or may have stridor and other symptoms, depending on the mechanism of injury.
Blunt or penetrating injuries to the larynx are more severe compared to soft tissue injury, and patients often present with stridor, subcutaneous emphysema, and hemoptysis. This is due to the shearing pressures on the laryngeal skeleton as a result of a high-velocity injury from a knife wound, motor vehicle crash, or motorcycle accident. The shearing pressures from blunt trauma may cause a combination of soft-tissue injuries, such as endolaryngeal mucosal tears or edema, and cartilage fractures.
Fractures of the laryngeal skeleton are rare, occurring in one out of every 14,000 patients after trauma and are usually caused by motor vehicle crashes or personal attacks where the neck is hyperextended. They can cause airway obstruction, as seen in a case of a 53-year-old man with acute comminuted mid anterior thyroid cartilage and cricoid cartilage fractures (Figs 1(a) to 1(b)).
Injuries to the vocal folds are less common, but occur in about 20 percent of patients with blunt laryngeal injuries. These can be either partial or complete, and can be caused by the shearing pressures of a blunt blow to the larynx or the shearing pressures from a high-velocity injury that crushes the vocal folds between the neck and the internal perichondrium.
Partial or complete vocal fold paralysis is the most common injury associated with a blunt laryngeal injury. This can lead to a tracheostomy or nasogastric tube until the larynx has fully recovered. The recurrent and superior laryngeal nerves may also sustain damage during repair of the damaged vocal fold, which may lead to dysphonia or aspiration.
The most important symptom of laryngeal trauma is a lack of breath when the patient tries to speak or breathe. This is a serious problem that can be fatal, so the patient should always be brought to an emergency room for assessment and treatment of any laryngeal or tracheal trauma.
After a blow to the larynx, a patient can present with a range of symptoms from stridor, hepatoma, and subcutaneous emphysema to respiratory failure or chest pain. The patient may also have tenderness to palpation of the laryngeal skeleton.
Acute supraglottic edema is another common symptom of a soft-tissue injury. This can be caused by an impact from a motor vehicle crash, a personal attack, or the shearing pressures from hyoid fractures or submucosal endolaryngeal injuries. A radiologist should carefully examine the adjacent soft tissues to determine the degree of mucosal laceration, tearing, and mass effect. If asymmetry is present, then multidetector CT should be performed to evaluate the adjacent soft tissues and the lateral paralaryngeal space.
If a patient has an undiagnosed chronic oesophageal injury, then a portable roentgenogram is the preferred test to collect information about this in a stable condition after securing the airway. An evaluation under anesthesia is typically required for this.
