Chapter 16. Frontal Sinus Fractures

• History of head trauma.
• Visible open fracture or fracture on computed tomography (CT) scans or plain X-rays.

The frontal sinus begins as an outgrowth of the nasal chamber in utero but does not begin to invade the vertical portion of the frontal bone until the 4th year of life. The sinus attains adult configuration at age 15 and typically reaches adult size by age 20. A variable structure, the frontal sinuses are typically asymmetric and may be unilateral (10%) or absent altogether (5%).

The anterior wall of the fully developed frontal sinus is a thick bony arch that can withstand between 800 and 2200 pounds of force. The force required to fracture this robust structure often leads to multiple injuries; therefore, a full trauma workup of all patients with frontal sinus fractures is paramount. As with all trauma patients, the airway, circulatory system, and other organ systems must be evaluated upon arrival. All patients require ophthalmologic and neurologic examination as well as radiographic and clinical examination of the cervical spine. Intracranial injury (40–50%) and other facial fractures (75–95%) are among the most commonly associated injuries in patients with frontal sinus fractures.

Motor vehicle accidents are the most common mechanism of injury for patients with frontal sinus fractures, accounting for 60–70% of all frontal sinus fractures. Assault typically requires the use of a blunt object to fracture the frontal sinus; fists alone rarely generate sufficient force. Other mechanisms of injury include industrial accidents, recreational accidents, and gunshot wounds. Young men in their third decade of life are most at risk for frontal sinus fracture. In one study, 30% of patients with frontal sinus fractures had blood alcohol levels over the legal limit or positive urine toxicology screens.

The anterior wall of the frontal sinus is significantly thicker than the posterior wall. Injuries that provide enough force to fracture the anterior wall of the frontal sinus often have enough force to fracture the posterior wall as well.

The use of seatbelts and airbags for passengers and drivers can decrease the incidence of severe head trauma and frontal sinus fractures. Patients in automobile accidents in which airbags are deployed have a significant decrease in the number of facial fractures. Estimates are that only 15% of young patients with frontal sinus fractures resulting from automobile accidents were wearing a seatbelt; less than 10% of patients with frontal sinus fractures from motorcycle accidents were wearing a helmet. The use of helmets with motorcycles, with bicycles, at appropriate sporting events, and in industrial situations also can protect the frontal sinuses.