Skull Fracture Treatment & Management

Adults with simple linear fractures who are neurologically intact do not require any intervention and may even be discharged home safely and asked to return if symptomatic. Infants with simple linear fractures should be admitted for overnight observation regardless of neurological status. ^[3] Neurologically intact patients with linear basilar fractures also are treated conservatively, without antibiotics. Temporal bone fractures are managed conservatively, at least initially, because tympanic membrane rupture usually heals on its own.

Simple depressed fractures in neurologically intact infants are treated expectantly. These depressed fractures heal well and smooth out with time, without elevation. Seizure medications are recommended if the chance of developing seizures is higher than 20%. Open fractures, if contaminated, may require antibiotics in addition to tetanus toxoid. Sulfisoxazole is a common recommendation.

Types I and II occipital condylar fractures are treated conservatively with neck stabilization, which is achieved with a hard (Philadelphia) collar or halo traction.

The role of surgery is limited in the management of skull fractures. Infants and children with open depressed fractures require surgical intervention. Most surgeons prefer to elevate depressed skull fractures if the depressed segment is more than 5 mm below the inner table of adjacent bone. Indications for immediate elevation are gross contamination, dural tear with pneumocephalus, and an underlying hematoma. At times, craniectomy is performed if the underlying brain is damaged and swollen. In these instances, cranioplasty is required at a later date. Another indication for early surgical intervention is an unstable occipital condylar fracture (type III) that requires atlantoaxial arthrodesis. This can be achieved with inside-outside fixation. ^[31]

In a retrospective study by Bonfield et al, the majority of pediatric skull fractures were found to be managed conservatively, and of those requiring surgical intervention, fewer than half of the surgeries were performed solely for skull fracture repair only. Surgical intervention was more likely in patients who were hit in the head with an object or were involved in a motor vehicle crash. Frontal bone fractures were more likely to necessitate repair, and those patients treated for traumatic brain injury had a greater incidence of 2 or 3 bones involved in the fracture. Most of the complications that occurred were related to the underlying trauma, not the surgery. In addition, none of the patients who underwent intervention for repair of only skull fracture had a worsening of neurologic status. ^[32]

Delayed surgical intervention is required in ossicular incongruences resulting from a longitudinal skull base fracture of the temporal bone. Ossiculoplasty may be needed if hearing loss persists for longer than 3 months or if the tympanic membrane has not healed on its own.

Another indication is persistent CSF leak after a skull base fracture. This requires precise detection of the site of leak before any surgical intervention is instituted. Generally, posttraumatic CSF leaks are treated conservatively, but for patients who do not respond to conservative treatment, surgical closure of the CSF fistula may be necessary. ^{[33, 34]}  

In addition, the rate of meningitis after skull base fracture in children has been found to be low, making prophylactic antibiotics or pneumococcal vaccine most often unnececessary. ^[33]

 

Blind probing of skull wounds should be avoided. Patients are prepared for surgery, and exploration is performed in the operating suite under direct vision to prevent loose pieces of bone from damaging the underlying brain. Patients with open contaminated wounds are treated with tetanus toxoid and broad-spectrum antibiotics, especially in a delayed presentation.

Overview

To maintain intracranial pressure, mannitol (1 g/kg) may be given at the beginning, and the PaO₂ should be kept at 30-35 mm Hg during the surgery. Patients should be secured firmly to the table, allowing Trendelenburg or reverse Trendelenburg positioning if required. A lazy "S" or a horseshoe-shaped incision is made over the depression. A bicoronal incision is preferred for forehead depressions.

Bony fragments are elevated, and the dura is inspected for any tears. If a dural tear is found, it should be repaired. Special attention is given to hemostasis to prevent postoperative epidural collection. Bony fragments are soaked in antibiotic/isotonic sodium chloride solution and are reassembled. Larger pieces may be wired together. Alternatively, titanium mesh also may be used to cover the defect. Methyl methacrylate can be used instead of the bone pieces, but this should be avoided in children. Indeed, absorbable bone plates and screws are recommended for use in children.

Venous sinus tears

Depressed fracture over a venous sinus poses a unique situation requiring special attention. The decision to operate is based on the neurological status of the patient, the exact location of the sinus involved, and the degree of venous flow compromise. A preoperative angiogram with venous flow phase or magnetic resonance angiography is recommended whenever a depressed fracture is thought to be over a venous sinus. Useful data regarding the position and extent of occlusion and transverse sinus dominance is obtained that can affect decisions regarding surgery.

A neurologically stable patient with a closed depressed fracture over a venous sinus should be observed. A patient with an open depressed fracture over a patent venous sinus who is neurologically stable should undergo skin debridement without elevation of the fracture, but if the patient is neurologically unstable, urgent elevation of the depressed fragment is required. On the other hand, if the patient is neurologically stable and the sinus is thrombosed, it can be assumed that ligation of the sinus can be tolerated.

Usually, the anterior one third of the superior sagittal sinus can be ligated without any consequences; however, tears in the posterior two thirds need repair, either primarily or with a galea or pericranium patch. Alternatively, a piece of muscle or Gelfoam may be sutured over the sinus.

Special surgical techniques are used when a skull fracture communicates with mastoid or frontal air sinuses. The communication of the intracranial space with the outside world needs to be eliminated. ^[35]

Other than the usual immediate postoperative care, the risk of intracranial hematoma and venous sinus thrombosis should be kept in mind in contaminated depressed fractures.

Adults with simple linear fractures of the vault, without any loss of consciousness at the time of initial presentation and with no other complications, do not require long-term follow-up. On the other hand, infants with similar fractures with dural tears need to be monitored more closely because of the possibility of the skull fracture expanding.

Patients with contaminated open depressed skull fractures treated surgically should be monitored with repeat CT scans a few times over the next 2-3 months to check for abscess formation. Follow-up also is dictated by the complications associated with skull fractures, for example, seizures, infections, and removal of bone pieces at the time of initial debridement.

Failure to recognize skull fracture has more consequences than the complications resulting from treatment. The chance of a concomitant cervical spine injury is 15%, and this should be kept in mind when assessing a patient with skull fracture.

Linear skull fracture

In infants and children, a simple linear fracture, if associated with a dural tear, can lead to subepicranial hygroma or a growing skull fracture (leptomeningeal cyst). This may take up to 6 months to develop, resulting from the brain pulsating against a dural defect that is larger than the bone defect. Repair of such a defect is performed using a split-thickness bone graft. Growing skull fracture has also been reported in literature following a stab wound to a gravid abdomen in the last trimester. ^[36]

According to Singh et al, early diagnosis of growing skull fracture can be made on the basis of 4 criteria ^[37] :

• Age < 5 years with cephalhematoma

• Bone diastasis 4 mm or more

• Underlying brain contusion

• Contrast MRI showing dural tear and herniation of the brain matter (dural tear with herniation of the brain matter is the main etiopathogenic factor for the development of growing skull fracture)

A fracture line crossing over a vascular groove, such as the middle meningeal artery, may form an epidural hematoma. ^[38] Similarly, a fracture line that crosses over a suture may cause sutural diastasis.

Basilar skull fracture

The risk of infection is not high, even without routine antibiotics, especially with CSF rhinorrhea. Facial palsy and ossicular chain disruption associated with basilar fractures are discussed in the Clinical section. However, notably, facial palsy that starts with a 2- to 3-day delay is secondary to neurapraxia of the VII cranial nerve and is responsive to steroids, with a good prognosis. A complete and sudden onset of facial palsy at the time of fracture usually is secondary to nerve transection, with a poor prognosis.

Other cranial nerves also may be involved in basilar fractures. Fracture of the tip of the petrous temporal bone may involve the gasserian ganglion. An isolated VI cranial nerve injury is not a direct result of fracture, but it may be affected secondarily because of tension on the nerve. Lower cranial nerves (IX, X, XI, and XII) may be involved in occipital condylar fractures, as described earlier in Vernet and Collet-Sicard syndromes (vide supra). Sphenoid bone fracture may affect the III, IV, and VI cranial nerves and also may disrupt the internal carotid artery and potentially result in pseudoaneurysm formation and caroticocavernous fistula (if it involves venous structures). Carotid injury is suspected in cases in which the fracture runs through the carotid canal; in these instances, CT-angiography is recommended.

Depressed skull fracture

In addition to the risk of infection in contaminated depressed skull fractures, a risk of developing seizures also exists. The overall risk of seizures is low but is higher if the patient loses consciousness for longer than 2 hours, if an associated dural tear is present, and if the seizures start in the first week of injury.

Although skull fractures carry a significant potential risk of cranial nerve and vascular injuries and direct brain injury, most skull fractures are linear vault fractures in children and are not associated with epidural hematoma. Most skull fractures, including depressed skull fractures, do not require surgery. Hence, all of the potential complications listed are associated with a graver prognosis if the primary fracture is missed during the diagnostic workup.

In a study by Hassan et al of nondepressed skull fracture in young children, children 5 years or younger with nondepressed skull fractures and a normal neurologic examination result at admission were found not to develop neurologic deterioration. ^[39]

Controversy exists in the use of antibiotics for fractures and the need to elevate a depressed skull fracture. The use of antibiotics generally is not required unless the open fracture is obviously contaminated. Similarly, whether to elevate a depressed skull fracture is mostly the surgeon's choice, dictated by the need for cosmesis. ^[40]

The use of resorbable bone plates cross-linked with Bone matrix protein-2 (BMP-2) is touted as a novel method of delivery and may enhance fracture healing. ^[41] Another delivery system with scaffolds that deliver plasmid DNA encoding for bone morphogenetic protein-4 (BMP-4) has been tested in rodents and has shown promise.