Traumatic brain injury (TBI) is a disruption in the normal function of the brain that can be caused by physical trauma. TBIs are classified as either “closed”, meaning the skull remains intact, or “open”, meaning the skull has been fractured.[1]. TBIs are further classified as mild, moderate, or severe. Mild TBI is often referred to as concussion. Severe brain injury can cause coma, permanent disability, or death.[2]
What is traumatic brain injury?
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•Last Updated: May 16, 2025
Traumatic brain injury (TBI) is a disruption in brain function caused by physical trauma and is classified as either closed or open based on whether the skull is penetrated. TBIs are further categorized as mild, moderate, or severe. Mild TBI is commonly known as a concussion, and severe cases can lead to coma, permanent disability, or death.