Battle’s sign refers to ecchymosis (bruising) over the mastoid process, located behind the ear. It is a key external indicator of a basilar skull fracture, often overlooked or concealed by hair. This type of fracture may not be visible on routine skull X-rays and, if untreated, can lead to serious complications including cranial nerve injury, meningitis, or damage to the brainstem.

Pathophysiology

The appearance of Battle’s sign results from bleeding due to tissue damage around the mastoid area following a traumatic force to the skull base. Blood from the fracture site migrates to the mastoid region, typically becoming visible 24–36 hours after injury, and may persist for several days to weeks.

Clinical Evaluation

A comprehensive neurologic and physical examination is crucial. Key steps include:

• History: Assess for recent head trauma, such as motor vehicle accidents or falls.

• Level of Consciousness (LOC): Evaluate the patient’s mental status and responsiveness.

• Vital Signs: Monitor for signs of increased intracranial pressure (ICP), such as widening pulse pressure or bradycardia.

• Cranial Nerve Examination: Pay special attention to cranial nerves II, III, IV, VI, VII, and VIII.

• Pupillary Response and Motor/Verbal Responses: Compare findings to the Glasgow Coma Scale (GCS).

• CSF Leak Detection: Look for clear fluid drainage from the nose or ears, or signs of postnasal drip. Confirm CSF using glucose test strips (positive for CSF, negative for mucus).

Additional signs may include periorbital ecchymosis (raccoon eyes), hemotympanum, epistaxis, anosmia, tinnitus, vertigo, and nystagmus.

Diagnostic investigations

• Imaging: CT scan of the head is preferred to detect fracture lines and assess associated brain injuries. Skull X-rays may be of limited diagnostic value.

• Laboratory Tests: CSF analysis if leakage is confirmed.

Management and monitoring

• Initial Care: Bed rest with the head of the bed flat to reduce CSF leakage. Avoid procedures such as nasogastric intubation that may introduce infection.

• Observation: Close monitoring of neurologic signs, LOC, and vital signs.

• Surgical Intervention: In cases of persistent CSF leakage or large dural tears, craniotomy and dural repair may be required.

Patient Education and Counseling

• Instruct the patient (or caregiver) on symptoms requiring immediate medical attention, such as changes in consciousness or breathing difficulties.

• Advise against nose-blowing and unnecessary physical activity.

• Discuss pain management using acetaminophen and the potential need for surgery.

Pediatric Considerations

Battle’s sign in children should raise suspicion for non-accidental trauma (child abuse). Health care providers are obligated to report any suspected abuse per institutional and legal protocols.

Summary

Battle’s sign, bruising behind the ear, is a key clinical indicator of a basilar skull fracture and may be the only visible sign. Prompt recognition, neurologic assessment, and imaging are critical to prevent complications.

References (Vancouver Style):

1. Fugate JE, Wijdicks EFM, Mandrekar J, Claassen DO, Manno EM, White RD, et al. Predictors of neurologic outcome in hypothermia after cardiac arrest. Ann Neurol. 2010;68(6):907–914.

2. Perry JJ, Stiell IG, Sivilotti ML, Bullard MJ, Emond M, Symington C, et al. Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: Prospective cohort study. BMJ. 2011;343:d4277.