Battle’s Sign

Named after a British doctor, Battle’s sign — also known as mastoid ecchymosis — is a physical sign of trauma to the head that might be suggestive of brain trauma. Ecchymosis is bruising which appears on the surface of the skin and is caused by the escape of blood into the tissues from ruptured blood vessels. Battle’s sign bruising appears behind one or both ears and is one indication of a basilar skull fracture caused by acute trauma to the head. Battle’s sign will normally develop within 24 to 36 hours after head trauma and might be visible for several weeks. A blow to the head strong enough to produce Battle’s sign could cause injury to the cranial nerves, brain stem, and lead to intracranial hemorrhage and even death.