Battle’s Sign: Definition, Etiology, Epidemiology, Pathophysiology, Evaluation and Management

Also called a battle sign, it is defined as bruising in the mastoid process.

It is the retroauricular or mastoid ecchymosis that is usually the result of a head trauma.

The battle sign derives its name from Dr. William Henry Battle, who initially described it in the late 1800s. He was an English surgeon who initially described ecchymosis in 17 patients who had head injuries with fractures at the back of the skull base.

Their description noted that significant head trauma was involved in developing the sign and may indicate significant internal injury to the brain and not just the posterior cranial vault or mastoid.

Etiology

One of the major problems associated with the battle sign is that it takes 1 to -2 days for the sign to appear and is therefore not helpful in the initial management of head trauma .

The naming of the battle sign has caused a lot of confusion in recent years. Many believe that the sign gets its name from fighting or battling as a mechanism to obtain injury rather than credit being given to Dr. Battle.

Also, although Dr. Battle is credited with the discovery and has his name on the sign, he was not the first to notice it. Sir Prescott G. Hewett, an English surgeon, had written about the association before Dr. Battle.

The battle sign can be mistaken for an extended hematoma from a mandibular condyle fracture, which is a less serious injury.

Another issue related to the battle sign is that there was a recent case report showing mastoid ecchymosis associated with hepatic encephalopathy in the absence of trauma.

This case means that the battle sign may not be as specific for head trauma as was initially thought. However, more research is needed on the association between hepatic encephalopathy and mastoid ecchymosis.

epidemiology

Basilar skull fractures are present in only 4% of patients with severe head injuries. An increase in predilection between sex or any race has not been reported.

The battle sign typically correlates with blunt head trauma; This is usually accidental, but can also be present in non-accidental head trauma, including child abuse.

In general, most skull fractures are linear and tend to be more common in children. The temporal bone is involved in the majority of skull fractures (45%), followed by basilar skull fractures (20%).

When a depressed skull fracture occurs, it is usually an open fracture, usually requiring surgery as soon as possible.

Pathophysiology

The battle sign is prominent when there is a fracture of the temporal stone bone. It can also be associated with runny nose and bruising of the eyes (raccoon eyes).

Depending on the severity of the head injury, the patient may also have loss of consciousness and a depressed Glasgow Coma Scale (GCS).

History and physics

The battle sign presents as ecchymosis over the mastoid process, located behind the ear. It is usually associated with the cuteness of the area as well.

Other findings that may be seen to indicate a basilar skull fracture are raccoon eyes (periorbital ecchymosis), hemotympanum (which is the presence of blood in the tympanic cavity of the middle ear), facial nerve injury, and laceration of the external auditory canal.

The battle sign is often present with a basilar skull fracture. The presence of the battle sign correlates with a positive predictive value of more than 75% for the presence of an associated basilar skull fracture.

In multiple studies, the battle sign was associated with a positive predictive value of 66% for intracranial injuries and 100% for skull base fractures.

Evaluation

The sign of battle is a clinical sign. No further evaluation is needed to diagnose the sign. However, since the battle sign correlates with an underlying skull fracture, the images are generally justified when observing the battle sign.

The initial evaluation is with a noncontrast CT scan, although linear or undisplaced fractures may not be detectable, requiring an additional imaging. If presentation is delayed and infection is suspected, a CT or MRI with contrast may be helpful.

It is vital to be checked for nosebleeds to rule out a CSF leak; This can be done by testing for the presence of tau transferrin or glucose level.

Treatment / Management

In general, treatment after a skull fracture depends on the type of injury. Patients with linear fractures who do not have neurological deficiencies and who have a GCS of 14 or more can be safely discharged home after a period of observation in the emergency room.

However, the patient must be available for follow-up if he becomes symptomatic. Children with linear fractures should be admitted overnight regardless of the absence / presence of neurological deficits.

Surgery is usually necessary when patients have depressed skull fractures. The current consensus is that the depressed segment is more than 5 mm below the internal table of the adjacent bone, that the patient should undergo surgery to elevate that bone segment.

Other indications for surgery include underlying hematoma, severe infection / contamination, and dural tear with pneumocephalus.

Patients should be treated with tetanus toxoid and broad-spectrum antibiotics if they have an open wound or if presentation has been delayed.

Basilar skull fractures are secondary to trauma, and therefore management requires a thorough evaluation of the trauma. Admission for observation is usually necessary with additional management determined on the basis of the fracture.

The battle sign itself will fade and heal over time, although it may take several weeks for the bruise to clear. When the battle sign is present, the patient is more likely to have a slower head injury recovery than expected.

Complications

When patients show signs of battle, it is vital to rule out an associated cervical injury. The data reveal that 15% of patients with a basilar skull fracture have an associated cervical injury.