Primary Types of Skull Frontal Fractures

Anatomical Classification

The American College of Radiology notes that anterior table fractures involve only the outer cortical bone of the frontal sinus, representing approximately one-third of all frontal sinus fractures 1, 2
The American College of Radiology states that posterior table fractures involve the thin bone separating the frontal sinus from the anterior cranial fossa, which is more delicate and easily fractured 1, 2
The American College of Radiology reports that combined anterior and posterior table fractures involve both tables simultaneously, representing approximately two-thirds of all frontal sinus fractures 1, 2

Isolated frontal bone fractures are limited to the frontal bone without extension, as noted by the American College of Radiology 1, 2
Fractures with nasofrontal duct involvement can cause nasofrontal duct occlusion, according to the American College of Radiology 1, 2
Fractures with cribriform plate involvement can result in CSF leak or chronic sinusitis, as stated by the American College of Radiology 1, 2
Fractures with orbital roof involvement penetrate the lateral part of the frontal sinus floor, as reported by the American College of Radiology 1, 2

Displaced posterior table fractures often indicate disruption of the underlying dura and communication between the frontal sinus and anterior cranial fossa, as noted by the American College of Radiology 1, 2, 3
Injuries to the nasofrontal duct can lead to potential mucocele formation and possibly osteomyelitis, according to the American College of Radiology 1, 2
Fractures through the medial aspect of the frontal sinus floor may result in cerebrospinal fluid leak or chronic sinusitis, as stated by the American College of Radiology 1, 2
Frontal bone fractures are often associated with intracranial injuries in 56-87% of cases, requiring comprehensive evaluation, as reported by the American College of Radiology 1, 2, 3

The American College of Radiology recommends multidetector CT (MDCT) without contrast as the gold standard for diagnosing frontal bone fractures, providing superior delineation of osseous and soft-tissue structures 1, 2, 4
CT head is complementary to maxillofacial CT for complete characterization of frontal bone injuries and associated intracranial injuries, as noted by the American College of Radiology 1, 2, 4
3D reconstructions are particularly valuable for surgical planning and better characterization of complex fractures, according to the American College of Radiology 1, 2, 4

CT maxillofacial without contrast is the gold standard initial imaging modality, providing superior delineation of osseous structures and detection of subtle nondisplaced fractures, according to the American College of Radiology 5
Complementary CT head without contrast is essential since 56-87% of frontal bone fractures have associated intracranial injuries, with 8-10% requiring surgical intervention for subdural or epidural hematoma, as recommended by the American College of Radiology 5
3D reconstructions are critical for surgical planning and characterizing complex fractures, significantly improving surgeon confidence, as stated by the American College of Radiology 5
Evaluate for cervical spine injury, present in 6-19% of significant maxillofacial trauma cases, according to the American College of Radiology 6

Surgical exploration via bifrontal craniotomy with sinus cranialization or obliteration is the standard approach for combined anterior and posterior table fractures with CSF leak or nasofrontal duct obstruction, as recommended by the American College of Radiology 5
Nasofrontal duct involvement requires surgical intervention to prevent mucocele formation and osteomyelitis, according to the American College of Radiology 5
Cribriform plate involvement mandates surgical exploration due to risk of CSF leak and chronic sinusitis, as stated by the American College of Radiology 5
Orbital roof involvement requires evaluation for globe injury and extraocular muscle entrapment, according to the American College of Radiology 5

Definitive treatment should be performed as early as safely possible once life-threatening injuries are stabilized, with management of ongoing hemorrhage or intracranial hypertension taking precedence over frontal bone fracture repair, as recommended by the Anaesthesia journal 7

The posterior table is thin and delicate, easily fractured despite the anterior table's ability to withstand up to 1,000 kg of force, as noted by the American College of Radiology 5
Medial frontal sinus floor fractures typically involve the cribriform plate, requiring heightened vigilance for CSF leak, according to the American College of Radiology 5

Monitor for delayed complications including mucocele formation, osteomyelitis, and chronic sinusitis, as recommended by the American College of Radiology 5

The American College of Radiology recommends multidetector CT (MDCT) of the maxillofacial region without contrast as the mandatory initial imaging study for any suspected frontal bone fracture, replacing plain radiographs as the gold standard. 8
MDCT provides high‑resolution, thin‑section images that delineate both bone and soft‑tissue structures, enabling detection of subtle nondisplaced fractures. 8
Multiplanar and three‑dimensional reconstructions from MDCT improve characterization of complex frontal bone fractures and enhance surgeon confidence during operative planning. 8
MDCT acquisition is faster than conventional radiography or MRI and is less dependent on patient positioning, facilitating rapid trauma assessment. 8

Plain radiographs miss approximately 3 % of skull fractures that are visible on CT, and half of those missed cases subsequently develop epidural hematomas; overall radiograph accuracy ranges from 53 % to 82 %. 9
CT has completely supplanted plain radiographs because radiographs cannot fully characterize fracture extent, detect nasofrontal duct involvement, or identify intracranial pathology. 9

Cervical spine CT should be added in high‑velocity trauma because cervical spine injuries are present in 6 %–19 % of patients with significant maxillofacial trauma. [10][9]
Frontal bone fractures often result from an anterior force that drives the cervical spine into extension, making concomitant cervical spine injury common in high‑energy mechanisms. [8][9]

MRI is reserved for scenarios where CT cannot adequately characterize findings, such as unexplained cranial nerve deficits, suspected cerebrospinal fluid leak from skull‑base fractures, or evaluation of herniated intracranial contents. 8