Head trauma can result in a skull fracture and is a common cause of morbidity and mortality in children. It is a regular presentation in the Paediatric Emergency Department (PED) and primary care. Children are more susceptible to head trauma and skull fracture than adults. A child's head size is approximately 18% of the total body surface area in infancy. This will decrease to roughly 9% by adulthood. Generally speaking, a child's skull is thinner and more pliable, thus providing less protection to the brain.
Causes of head injury and skull fracture can be separated into accidental and non-accidental injuries. Commonly, head injuries are caused by a fall. Other causes can include motor vehicle accidents (MVA), sports-related injuries, or other direct blows to the head. Occasionally, depressed "ping-pong" fractures can occur in newborns due to injury at birth. A non-accidental injury is important for clinicians to identify in children who present with a head injury and subsequent skull fracture. This is particularly important in the non-mobile infant. A meta-analysis of 12 studies of skull fractures in abuse have shown a skull fracture to be a positive predictive value of 20.1% in suspected or confirmed abuse cases.
Head injury is a very common presentation to the PED and is the most common cause of lethal trauma in children. Fortunately, the majority (80% to 90%) of head injuries can be classified as mild. Very few injuries are life-threatening or require neurosurgical intervention. The incidence of skull fracture in children following head injury ranges from 2% to 20%, and further epidemiological study is needed for more accurate incidence and prevalence rates. Skull fracture has been shown to be more common in children under the age of 2 years following head trauma. A fracture of the calvarium (skull cap) is more common than one at the base of the skull.
The skull can be divided into the calvarium and the skull base. The calvarium is made up of the frontal, parietal, occipital, and temporal bones. The skull base is composed of the sphenoid, palatine, and maxillary bones along with portions of the temporal and occipital bones.
Types of Skull Fracture
LinearThis is the most common simple type. It is typically in the temporal or parietal area.
DepressedThis is usually caused by a direct blow to the head and requires a neurosurgical opinion. A depressed skull fracture can sometimes be referred to as a ping-pong fracture.
OpenAn open fracture carries a high risk of infection.
BasalBasal fractures involve any of the bones of the base of the skull. Basal fractures are more complicated due to underlying structures such as cranial nerves and sinuses which can lead to hearing loss, facial paralysis, or decreased sense of smell. They also can pose a risk for meningitis.
DiastaticDiastatic fractures occur when there is a separation of the cranial sutures, most commonly with the lambdoid suture.
GrowingA growing fracture describes herniation of the brain through the broken dura following a skull fracture (often diastatic). It usually presents later and grows as the brain herniates through the gap, as a persistent swelling or pulsatile mass. It is uncommon.
A concise history can assist the clinician when determining whether a child presenting with a head injury has a high risk of a skull fracture or traumatic brain injury.
Important factors include:
Examination should include:
As a safeguarding procedure, the clinician always needs to carefully consider whether the described mechanism of injury is consistent with the developmental age of the child and the clinical findings.
Skull fractures can be identified on plain radiography, CT, ultrasound, and MRI. Although practice varies throughout the literature, current guidance discourages the use of skull radiograph and advises the use of CT scan as the first-line investigation of choice if skull fracture is suspected. In few cases, a well, asymptomatic child with a localized head injury that is suspicious for fracture may be a candidate for skull x-ray instead of CT. The risks associated with CT scan in a child also should be considered. The younger the child, the greater the risk of malignancy later in life as a result of exposure to ionizing radiation. There also are associated risks with the sedation or anesthesia that may be required to perform a CT on a child.
Multiple clinical decision rules exist to guide clinicians when a child with a head injury requires CT; the PECARN (Paediatric Emergency Care Applied Research Network) head injury algorithm, the CATCH (Canadian Assessment for Tomography of Childhood Head Injury) rule and the CHALICE (Children's Head Injury ALgorithm for prediction of Clinically Important Events) rule. Signs of skull fracture that warrant investigation with CT include signs of basal skull fracture, a palpable fracture, a swelling, bruise or hematoma measuring greater than 5 millimeters or suspicion of a depressed skull fracture.
Ultrasound can be used to identify skull fractures in younger patients although it is not widely used and further studies are needed to assess its efficacy. MRI could prove a useful investigation without radiation exposure, but its use is also limited, due to availability in the acute setting.
Repeat CT imaging for patients with isolated skull fracture is not deemed necessary unless worsening clinical indicators develop.
Some centers have safeguarding policies in place to guide the need for further investigation for non-accidental injury in younger children and infants with a skull fracture. Routine skeletal surveys in this population with isolated skull fracture may only yield results in the non-mobile infants (less than 6 months) unless there are other indications. In these children, a skull radiograph may be required in addition to a CT as it has a higher sensitivity for old fractures.
Management of skull fractures depends on the location and type of fracture along with the presence (or absence) of underlying brain injury. Most skull fractures that are simple linear fractures without underlying brain injury and will require no intervention. Various practice patterns exist in regard to recommendations for observation periods or close outpatient followup. There are also variations whether skull fractures should be treated similar to concussions. In fact, one study has shown that most fractures requiring intervention do not necessarily require intervention for the fracture alone, but rather for an associated underlying injury. Younger patients, and symptomatic patients, should be admitted to the hospital for an observation period. Variations to this practice are supported by multiple studies that have shown that asymptomatic children with simple fractures can be safely discharged from the emergency department. However, in each of these cases, a CT of the head had been performed to rule out an underlying brain injury.
Frontal bone fractures are more likely to require neurosurgical repair. A depressed fracture usually requires intervention. Indications for a neurosurgical elevation of a depressed fracture include depression of 5 millimeters or more, dural injury, underlying hematoma, or gross contamination. An open fracture will likely require exploration and washout with antibiotic coverage. Basal skull fractures are usually managed conservatively unless there is persistent CSF leakage. A patient with a basal skull fracture should not have a nasogastric tube or nasal cannula. There is no evidence to support the role of prophylactic antibiotics in preventing meningitis, although, persistent CSF leak may increase the risk of meningitis.
Although head injury can lead to fatal brain injury and death, the majority of skull fractures are simple and can be managed conservatively. Head injury with a skull fracture, understandably, can generate huge parental anxiety, and clinicians need to be equipped with information to educate parents and allay fears. In addition, addressing concerns about safeguarding and non-accidental injury should be dealt with openly and in a professional manner. When discharge occurs directly from the emergency department, it should be to a safe environment with clear discharge instructions and return precautions.
A multidisciplinary approach should be considered in conjunction with trauma services, neurosurgery, general pediatrics, and social work. Close follow up is paramount to ensure safe outcomes. Any child suspected to be a victim of nonaccidental trauma should be reported per state law.