Frontal Bone Fracture Management in the ED

Anatomy

The frontal bone borders several bones on its external surface. Anteriorly and medially it joins the nasal bone to create the area called the nasion. Lateral to this, it joins the superior aspect of the maxillary bone bilaterally. Lateral from the maxillary bone, it connects to various bones that form the posterior aspect of the orbit. From medial to lateral, it connects to the lacrimal bone, the sphenoid bone, and the zygomatic bone. Posterior and lateral to the zygomatic bones, it connects again with the temporal surface of the greater wing of the sphenoid, then finally with the parietal bones posteriorly. The frontal bone alone creates the roof of the orbit. It also contains a small zygomatic process to connect with the zygomatic bone just lateral to the lateral wall of the socket.[1]

Two anatomically important landmarks are found on the external surface of the skull that the frontal bone contributes to: the bregma and the pterion. The bregma is the place where the sagittal and coronal sutures meet. The coronal suture is a syndesmosis that joins both parietal bones and the posterior aspect of the frontal bone. The frontal bone has involvement in formation of the pterion through joining of 4 cranial bones: frontal, sphenoidal, parietal, and temporal. Last, the anterior aspect of the frontal bone contains 2 frontal sinuses, each superior to the orbital roof.[1]

Younger patients have more elastic cartilaginous and bony structures in the face and a larger cranium-to-face ratio; thus, fractures in very young children are rare. The growth patterns of the face dictate age-specific fracture patterns that differ from adults.[4]

Frontal cranial bones have greater thickness than the more lateral temporal bones (6.15 cm in males, 7.13 cm in females, compared to 4.33 cm and 4.41 cm, respectively). As a result, these fractures require a more forceful mechanism of injury than other facial bone fractures; they occur less frequently than other forms of skull trauma and often present with concurrent injuries such as naso-orbito-ethmoid fracture, orbital injury, cerebrospinal fluid (CSF) leak, intracranial hemorrhage, and cervical spine fracture, among others. The potential for other potentially devastating injuries to occur along with frontal sinus fractures makes thorough evaluation of these patients imperative.[3]

Object and force

The type of object striking the face and the force behind the object are the main determinants of whether a person sustains soft tissue or bony injury. In automobile accidents, striking a hard dashboard is more likely to cause bony injury than striking a padded dashboard or an airbag. Striking the steering wheel concentrates the force more than striking the flat surface of the dashboard.[5] This also holds true for altercations with a bat, as compared to a bare fist or boxing glove. Penetrating injury from a shotgun at a distance is not likely to cause fractures. Bullets from low-velocity guns are likely to cause fractures; high-velocity bullets cause fractures and extensive soft tissue damage.

The amount of force needed to fracture different bones of the face has been studied; injuries have been divided into those that require high impact to fracture (greater than 50 times the force of gravity [g]) and those that require low impact to fracture (50 g or less). High impact include supraorbital rim, 200 g; symphysis of the mandible, 100 g; frontal-glabellar bone, 100 g; and angle of mandible, 70 g. Low impact include zygoma, 50 g, and nasal bone, 30 g.

Frontal bone and supraorbital ridge fractures require high-energy impact. Forces this strong may indicate intracranial injury. The frontal bone contains the frontal sinus, and fracture of only the anterior (outer) table or of both anterior and posterior (inner) tables is possible.[6] Associated fractures of the supraorbital ridge, the naso-ethmoidal complex, and other facial bones may occur.[7, 8]

Frontal bone fractures show a low frequency of occurrence at about 5-15% of all maxillofacial fractures, occurring as the result of high-velocity injuries such as those caused by motor vehicle accidents, sporting events, falls, falling objects, assaults, and penetrating trauma.[2]  These injuries most commonly occur in young males (92%), with a mean age of 20-31 years.[3]

Among all patients with facial fracture, less than 15% are children. Most facial injuries in children are limited to soft tissues, with only 10-15% of pediatric facial injuries resulting in facial fracture. However, more than half of all facial trauma presentations are associated with concurrent additional severe injuries beyond the face.[4]

Many minor facial traumas are treated at home and may be underreported; facial fractures are likely to cause significant pain and swelling and therefore are more likely to be accurately reported than soft tissue trauma to the face.[4]

Males are more likely to have facial fracture than females, especially during adolescence, when males are approximately twice as likely as females to present with fracture.[4]

Consider domestic violence in women with facial injuries not related to a motor vehicle crash.

Consider child abuse when facial injuries are found in children.

Facial fractures are rare among those younger than 6 years, in whom skull fractures are more likely to be the result of head or facial trauma. When facial fractures occur in children, roughly half are the result of motor vehicle collisions. Beyond motor vehicle collisions, bicycle accidents and sports injuries account for most remaining traumatic events in school-aged children; infants and toddlers are more likely to suffer from falls. Adolescent males are the demographic group most likely to be injured as the result of assault.[4]

Fracture location can be age-dependent due to both activities undertaken affecting the location of likely blunt trauma and differential areas of bone growth and laxity with age.[4]

Nasal fractures are generally thought to be the most common facial fractures, although they are likely underreported, as they do not necessitate evaluation at a trauma center—the source of most pediatric facial trauma data.[4]

Frontal bone fractures are associated with intracranial injury in 35-64% of cases, and with CSF leak in 18-36% of cases (this generally is seen in younger patients). Naso-orbito-ethmoid fractures are uncommon, representing only 1-8% of all pediatric fractures.[4]

In a retrospective review of facial fractures at a level 1 trauma center from 2000 to 2012 in 285 patients aged 18 years or younger, mean patient age was 14.2 years with a male predominance (77.9%). The mechanisms of injury were assault in 108 (37.9%), motor vehicle accident in 68 (23.9%), pedestrian struck in 41 (14.4%), fall in 26 (9.1%), sporting accident in 20 (7.0%), and gunshot injury in 16 (5.6%). The mean Glasgow Coma Scale score (GCS) on arrival to the ED was 13.7. The most common fractures were those of the mandible (29.0%), orbit (26.5%), nasal bone (14.4%), zygoma (7.7%), and frontal bone/frontal sinus (7.5%). Intracranial hemorrhage was present in 70 patients (24.6%). Fractures of the zygoma, orbit, nasal bone, and frontal sinus/bone were significantly associated with intracranial hemorrhage (P< 0.05), and fractures of the zygoma and orbit were significantly associated with cervical spine injury (P< 0.05).[9]

The prognosis for patients with frontal bone fracture is related to the extent of injuries sustained, as well as to the clinical condition of the patient. If many injuries are present, various specialists and subspecialists may be needed to treat the patient.[3]

Ultimately, isolated frontal sinus fractures have a good prognosis, regardless of whether or not the nasofrontal outflow tract or the posterior table is involved. Advancements in surgical technique and in equipment have improved the chances of preservation of the frontal sinuses, as well as patients’ anticipated quality of life.[3]

The prognosis for pediatric patients with facial trauma is generally good, although the more bones that are involved, the greater the chance of long-term deformity and need for surgical repair. Pediatric osteochondral tissues are adept at remodeling, and most patients heal well with minimal later discernible evidence of injury.[4]

The primary method of avoiding or mitigating frontal sinus fracture consists of consistent wearing of helmets during sporting activities involving rapid movement (cycling, driving, skiing, skateboarding, etc.), rapid projectile travel (baseball, cricket, softball, etc.), and full body contact (American football, ice hockey, lacrosse). Helmets should also be worn during activities involving heavy machinery or work in dangerous environments (eg, construction workers, industrial factory workers, soldiers).[3]

Although trauma typically is incidental, some methods remain to reduce the chance of occurrence and the severity of injuries. These involve evaluating potential risk of child abuse, suicidal tendencies, and risky social behaviors (including injurious sports or recreational activities).[4]

Adults and children alike see a decreased rate of injury or death when age- and size-appropriate car seats and restraints are used. Additionally, use of personal protective equipment should be encouraged for participation in recreational and sporting activities.[4]

Patients should be made aware of the high incidence of posttraumatic stress disorder associated with facial injuries and have resources available should symptoms occur.[10]

Given that maxillofacial fractures are the result of trauma, primary survey and attention to ABCs take priority.[7, 8, 11, 12, 13, 14, 15] Focus initially on patency of the airway, control of the cervical spine, and whether the patient is having difficulty breathing, and determine if the patient is experiencing symptoms of shock or neurologic impairment.

Obtaining a thorough and comprehensive history is imperative in the initial triage and management of patients with facial trauma. Due to the nature of these injuries, patients may not have the capacity to provide this information themselves, making it essential for providers to gather data from family, friends, witnesses, and first responders.[3]

Facial injuries may be distracting to both the patient and the examiner. Do not allow eye-catching injuries to the face to delay or prevent consideration and evaluation of other severe and life-threatening conditions.[4]

Follow advanced trauma life support (ATLS) concepts, particularly noting effects of facial injury on the potential for airway compromise, spinal or neck injuries, or other head trauma, including traumatic brain injury.[4]

Once life-threatening and other severe conditions are accounted for and stabilized, perform a more detailed facial structure evaluation.[4]

Obtain a thorough history of the following:

• Allergies

• Medications

• Medical history

• Last meal

• Events leading to injury

Ask the patient questions about the injury, including the following:

• Do you have epistaxis or clear fluid draining from the nares or ears?

• Did you lose consciousness?

• Have you had any visual problems, such as double or blurred vision?[16]

• Have you had any hearing problems, such as decreased hearing or tinnitus?

• Do your teeth come together normally? Are you able to bite down without pain?

• Do you have areas of numbness or tingling on the face?

• (In women) Was this injury caused by a partner? Do you feel threatened by anyone?

• (In children) Ask questions to discern whether child abuse is an issue.

Per the Advanced Trauma Life Support (ATLS) protocol, evaluation of trauma patients begins with assessment of the patient's airway, respiratory capacity, and circulatory status. While assessing the extent of the patient's disabilities, perform a thorough neurologic exam to calculate a Glasgow Coma Scale score, while assessing cranial nerve function and other focal deficits and bony injury to the calvarium.[3]

Avoid distraction by obvious or deforming injuries, and focus on establishing or maintaining a definitive airway, preserving respiratory status, and supporting circulatory volume. After initial stabilization, perform a thorough history and physical examination.[3]

Frontal bone fracture is suspected in patients who experience high-impact, blunt trauma and have a physical exam demonstrating step-off of the frontal bone or supraorbital ridge. Epistaxis or CSF leak merits further evaluation if the patient has a forehead injury.

Perform computed tomography (CT) scan of the head and facial bones. This is the most important test for determining structural involvement and for planning management. If a frontal sinus fracture is observed on CT, this indicates significant trauma, and it is imperative to search for corresponding injuries.[3]

Complete exam of the face is necessary because multiple injuries can occur easily. Portions of the exam specific for the frontal bone are marked with an asterisk (*)[17] :

• Inspect face for asymmetry; this is often easiest to do by looking down from the head of the bed.

• *Inspect open wounds for foreign bodies and palpate for bony injury.

• *Palpate bony structures of the supraorbital ridge and the frontal bone for step-off fractures.

• *Examine eyes thoroughly for injury, abnormality of ocular movements, and visual acuity.[16]

• Inspect nares for telecanthus and widening of the nasal bridge. Palpate for tenderness and crepitus.

• Inspect nasal septum for septal hematoma and clear rhinorrhea, which suggest cerebrospinal fluid (CSF) leak.

• Palpate zygoma along its arch as well as its articulations with frontal bone, temporal bone, and maxillae.

• Check facial stability by grasping teeth and hard palate, then gently pushing back and forth and up and down, while feeling for movement or instability of the midface.

• Inspect teeth for fracture and bleeding at the gum line—a sign of fracture through alveolar bone. Test for stability.

• Check teeth for malocclusion and step-off.

• Palpate the mandible for tenderness, edema, and step-off along its symphysis, body, angle, and condyle anterior to the ear canal.

• *Evaluate supraorbital, infraorbital, inferior alveolar, and mental nerve distributions for hypoesthesia and anesthesia.

The potential for other possibly devastating injuries to occur along with frontal sinus fracture makes thorough evaluation imperative.[3]

Identify any life-threatening injuries and stabilize the patient upon presentation.[3]

Surgical reconstruction will need to be carried out by appropriate specialists, who will vary depending on associated injuries and surgeon availability.[3]

After a comprehensive history and physical examination, the most important test for determining structural involvement and subsequent management is a non-contrast computed tomography (CT) scan of the head and facial bones. Various windows are available through CT imaging (osseous, soft tissue, heme windows), making evaluation of these and related injuries rapid and reliable.[3]

If a frontal sinus fracture is observed on CT, this indicates significant trauma, and it is imperative to search for corresponding injuries.[3]  Examine bone windows to evaluate the posterior table of the frontal sinus.

Obtain routine facial views, including Waters, Caldwell, and lateral projections. The Caldwell projection provides the best view of the anterior table; however, the posterior table is difficult to assess on any of the standard plain film views. If CT is available and is performed, no evidence suggests any additional benefit to be derived from plain film radiography.[3]

Consider angiography if the physician is concerned about possible vascular injury.[3]

Use ultrasonography to detect fractures by using a linear probe in a superficial mode. This test should be viewed as an adjunct to the previously mentioned modalities.[3]

Look for associated orbital rim and naso-ethmoidal fractures on CT scan.

Consider brain CT scan to exclude brain injury or an intracranial bleed.

Lab studies include direct lab studies toward workup of a trauma patient. If fracture is an isolated injury, obtain preoperative labs if surgery is planned.

Test clear rhinorrhea for glucose to help determine if it is CSF, as nasal secretions are normally low in glucose. If blood is present, this test is unreliable.

Blood-tinged fluid can be placed on filter paper to look for a double-ring sign of CSF around the blood; however, this technique is not reliable.

When dural leak causing CSF rhinorrhea is suspected yet cannot be proven, the following procedure, which generally is not performed in the ED, may be done: Inject fluorescein dye into the lumbar subarachnoid space. Examine the discharged nasal fluid 30 minutes later with a Wood lamp for fluorescence; fluorescence confirms CSF rhinorrhea.

ABCs are the first priority. Hold the airway open by chin lift, jaw thrust, or airway adjuncts, including endotracheal intubation.[18]

Because of concerns over intracranial placement of endotracheal tubes, avoid using the nasotracheal route for intubation if the patient has extensive facial damage, or if midface fracture is suspected.

Place the patient on a backboard with a collar if cervical spine injury is a possibility.

Treat patients with hypoventilation with intubation and bag ventilation.

Control actively bleeding wounds by applying a bandage with direct pressure.

ABCs take priority; reassess the airway frequently.

Do not focus solely on the obvious deformity, thereby failing to perform a complete primary survey.

Rapidly diagnose other life threats and undertake appropriate resuscitation. Follow with a complete secondary survey.

Diagnosis of frontal bone fracture in the ED is part of the secondary survey.

After initial stabilization, perform a thorough history and physical exam.

Perform a non-contrast CT scan of the head and facial bones. If a frontal sinus fracture is observed on CT, this indicates significant trauma, and it is imperative to search for corresponding injuries.[3]

Thoroughly evaluate the patient to avoid the possibility of missing other potentially devastating injuries.[3]

Select an appropriate management approach. Appropriate classification and indications for surgical repair of frontal sinus fractures remain controversial, and a variety of management strategies are available.[3]

Identify any life-threatening injuries and stabilize the patient upon presentation.[3]

Enlist the support of an interprofessional team for comprehensive management, depending on the extent of the injury. Surgical reconstruction will need to be carried out by appropriate specialists.[3]

If a frontal bone fracture is diagnosed, refer the patient to a neurosurgeon, as these injuries often are associated with intracranial injury.

Provide care for a patient with multiple injuries in collaboration with a surgeon who is experienced in trauma care.

The incidence of posttraumatic stress disorder is high in patients with facial injuries; consider consultation with a psychiatrist.[10]

Enlist the support of an interprofessional team for comprehensive management, depending on the extent of the injury. Surgical reconstruction will need to be carried out by appropriate specialists.[3]

Given that frontal bone fractures require extreme force, admitting all except those few patients with isolated, nondisplaced anterior table fractures is appropriate.

Management of frontal bone fracture takes into consideration the location and displacement of the fracture, as well as the presence or absence of any associated maxillofacial or other head injuries.[1]

Patients with depression of the inner table often require neurosurgical intervention to elevate the fragment.

Common surgical fixation options include the use of titanium plates/screws, titanium mesh/screws, or a combination of these methods to obtain an ideal open reduction internal fixation construct.[1]

Those with continued CSF leak may require a frontal sinus procedure involving ablation of the sinus and removal of the inner table to allow the frontal sinus to become part of the cranium. 

A CSF leak in patients with facial fracture can result in meningitis and other central nervous system complications. In a retrospective cross-sectional study of 1,287 patients admitted to a medical center with head and face injuries over a 7-year period (2004-2010), 17 had CSF leaks. Among patients with CSF leak, 8 (47%) were treated spontaneously, 2 (11.8%) were treated through lumbar drain placement, and 7 (41.2%) were treated by surgical intervention.[19]

Pediatric frontal sinus fractures are rare. A retrospective review of 39 patients aged birth to 18 years shows that fractures of the anterior or posterior table with displacement greater than one table-width were significantly associated with higher hospital costs, higher-velocity mechanisms of injury, lower Glasgow Coma Scale scores, nasofrontal outflow tract (NFOT) involvement, and CSF leak. According to the authors, pediatric patients without NFOT involvement can be managed with observation only, but those with NFOT involvement or persistent CSF leak should be treated with obliteration or cranialization, respectively, to reduce the risk of severe complications.[20]

Successful surgical management revolves around the concept of minimizing cosmetic deformity, maintaining normal sinus function, and avoiding short- and long-term complications.[2]

Complications of frontal bone fracture vary according to the extent of injury but can include frontal sinusitis, meningitis, mucocele, poor aesthetic outcome, brain abscess, frontal headaches, ophthalmoplegia, and/or local paresthesia.[3]

CSF leaks may continue, although most cease by 2-3 weeks after the injury. Observe the patient closely for signs and symptoms of meningitis or abscess formation.

A delay in operative management of frontal sinus fractures in patients requiring operative intervention was shown to be associated with increased risk for serious infection. A retrospective chart review of 242 consecutive patients with surgically managed frontal sinus fracture reported that serious infections included meningitis, encephalitis, brain abscess, frontal sinus abscess, and osteomyelitis. Delayed operative interventions were defined as procedures performed more than 48 hours after admission. Operative delay beyond 48 hours was independently associated with a 4.03-fold increased risk for serious infection; external use of a CSF drainage catheter and local soft tissue infection conferred 4.09-fold and 5.10-fold increased risk, respectively.[21]

Common postoperative complications include but are not limited to the following:

• Surgical site infection (SSI)
• Supraorbital nerve paresthesia
• Facial nerve paralysis (transient) ^[1]

In a retrospective review of pediatric facial fractures (285 patients 18 years or younger), the most common fractures were those of the mandible (29.0%), orbit (26.5%), nasal bone (14.4%), zygoma (7.7%), and frontal bone/frontal sinus (7.5%). Intracranial hemorrhage was present in 70 patients (24.6%), skull fracture in 50 (17.5%), cervical spine fracture in 10 (3.5%), and lumbar spine fracture in 11 (3.9%). Midface fractures and a depressed Glasgow Coma Scale score (GCS) showed a strong correlation with intracranial hemorrhage and cervical spine fracture. The mean GCS for patients with and without intracranial hemorrhage was 11.0 and 14.6, respectively (P< 0.05). The mean GCS for patients with and without cervical spine fracture was 11.2 and 13.8, respectively (P< 0.05). Researchers recommended that patients with midface fractures should be evaluated for intracranial hemorrhage and spine fracture if the GCS is abnormal.[9]

The primary method of avoiding or mitigating frontal bone fracture consists of consistent wearing of helmets during sporting activities involving rapid movement (cycling, driving, skiing, skateboarding, etc.), rapid projectile travel (baseball, cricket, softball, etc.), and full body contact (American football, ice hockey, lacrosse). Helmets should also be worn during activities involving heavy machinery or work in dangerous environments (construction workers, industrial factory workers, soldiers, etc.).[3]

Although trauma typically is incidental, some methods remain to reduce the chance of occurrence and the severity of injuries. These involve evaluating potential risk of child abuse, suicidal tendencies, and risky social behaviors (including injurious sports or recreational activities).[4]

Adults and children alike see a decreased rate of injury or death when age- and size-appropriate car seats and restraints are used. Additionally, use of personal protective equipment for participation in recreational and sporting activities should be encouraged.[4]

When airway control is needed, rapid-sequence induction is often the preferred method. Rapid-sequence induction utilizes medications to induce unconsciousness and muscle paralysis to facilitate intubation. A cricothyroidotomy kit should be at the bedside in case problems arise.

Medication for pain control is appropriate, including NSAIDs, narcotics, or local anesthetics.

Use of prophylactic antibiotics is controversial when a CSF leak is identified. This decision is usually left to the discretion of the specialist assuming care of the patient.

In cases of open wounds, administer tetanus toxoid if the patient is not up-to-date.

Class Summary

These drugs are used most commonly for relief of mild to moderately severe pain. Effects of NSAIDs in the treatment of pain tend to be patient specific, yet ibuprofen is usually the drug of choice (DOC) for initial therapy. Other options include flurbiprofen, ketoprofen, and naproxen.

Ibuprofen (Ibuprin, Advil, Motrin)

Usual DOC for treatment of mild to moderately severe pain, if no contraindications. Inhibits inflammatory reactions and pain, probably by decreasing activity of enzyme cyclooxygenase, which inhibits prostaglandin synthesis.

Naproxen (Anaprox, Naprelan, Naprosyn)

Relieves mild to moderately severe pain. Inhibits inflammatory reactions and pain by decreasing activity of enzyme cyclooxygenase, which decreases prostaglandin synthesis.

Ketoprofen (Oruvail, Orudis, Actron)

For relief of mild to moderately severe pain and inflammation.

Administer small dosages initially to patients with small bodies, older persons, and those with renal or liver disease.

Doses higher than 75 mg do not increase therapeutic effects.

Administer high doses with caution; closely observe the patient for response.

Flurbiprofen (Ansaid, Ocufen)

Provides analgesic, antipyretic, and anti-inflammatory effects. May inhibit cyclooxygenase enzyme, inhibiting prostaglandin biosynthesis.

Class Summary

Pain control is essential to quality care. It ensures patient comfort, promotes pulmonary toilet, and aids physical therapy regimens. Many analgesics have sedating properties that benefit patients who have sustained fractures.

Acetaminophen and codeine (Tylenol #3)

Drug combination indicated for treatment of mild to moderately severe pain.

Hydrocodone bitartrate and acetaminophen (Vicodin ES)

Drug combination indicated for relief of moderately severe to severe pain.

Oxycodone and acetaminophen (Percocet)

Drug combination indicated for relief of moderately severe to severe pain. DOC for aspirin-hypersensitive patients.

Morphine sulfate (Duramorph, Astramorph, MS Contin)

DOC for narcotic analgesia because of its reliable and predictable effects, safety, and ease of reversibility with naloxone.

Morphine sulfate administered IV may be dosed in a number of ways and commonly is titrated until desired effect is obtained.

Class Summary

Patients who may not have been immunized against Clostridium tetani products should receive tetanus immune globulin.

Tetanus immune globulin (TIG)

For passive immunization of any person with a wound that may be contaminated with tetanus spores.

Class Summary

This agent is used for tetanus immunization. Booster injection in previously immunized individuals is recommended to prevent this potentially lethal syndrome.

Tetanus toxoid adsorbed or fluid

Used to induce active immunity against tetanus in selected patients. Tetanus and diphtheria toxoids are the immunizing DOC for most adults and children >7 years of age. Booster doses must be administered to maintain tetanus immunity throughout life.

Pregnant patients should receive only tetanus toxoid, not a diphtheria antigen-containing product.

In children and adults, may be administered into the deltoid or mid-lateral thigh muscles. In infants, preferred site of administration is the mid-thigh laterally.