What is a TBI (Traumatic Brain Injury)? 

A Traumatic Brain Injury (TBI) is defined as an alteration in brain function, or other evidence of brain pathology, caused by an external force. The injury results in a change to the brain’s neuronal activity, which affects the physical integrity, metabolic activity, or functional ability of nerve cells in the brain. Traumatic impact injuries can be defined as closed (or non-penetrating) or open (penetrating). 

Frequent Causes: 
  • Falls
  • Assaults
  • Motor Vehicle Accidents
  • Sports/Recreation Injuries
  • Gunshot Wounds
  • Workplace Injuries
  • Military Actions (Blast Injury)

Types of TBI (Traumatic Brain Injury)?

Traumatic brain injuries may be classified as mild, moderate, or severe to indicate the initial severity of the injury. The type injury may be either diffuse or penetrating. 
A mild brain injury may be caused by direct blows to the head, gunshot wounds, sudden shaking of the head, or force from a whiplash-type injury. Both closed and open head injuries can produce a concussion. A concussion is the most common type of traumatic brain injury and causes a diversity of symptoms.
A concussion is:
  • caused when the brain receives trauma from an impact or a sudden momentum or movement change and the blood vessels in the brain may stretch and cranial nerves may be damaged.
  • A person may or may not experience a brief loss of consciousness (not exceeding 20 minutes). A person may remain conscious, but they may feel “dazed” or “punch drunk” or "out of it."
  • A concussion may or may not show up on a diagnostic imaging test, such as a CAT scan.
  • Skull fracture, brain bleeding, or swelling may or may not be present.
  • A concussion can cause injuries resulting in permanent or temporary damage.
  • It may take a few months to a few years for a concussion to fully heal.
A moderate brain injury is one that can be caused by a contusion which is a bruise (bleeding) on the brain or caused by a bump, blow, or jolt to the head or by a penetrating injury (such as from a gunshot) to the head. This type of injury may or may not require surgery depending upon severity.
A severe brain injury is one that may be caused by:
  • A “through-and-through” injury occurs when an object enters the skull, goes through the brain, and exits the skull. Through-and-through traumatic brain injuries include the effects of penetration injuries, plus additional shearing, stretching, and rupture of brain tissue.
  • Objects traveling at a low rate of speed through the skull and brain which can ricochet throughout the skull and widen the area of damage.
  • A penetrating injury to the brain occurs from the impact of a bullet, knife, or other sharp object that forces hair, skin, bone, and fragments from the object into the brain.
A severe brain injury may cause an individual to experience an unconscious state, where one appears to be in a deep sleep and cannot be aroused or respond purposefully. Assessments will typically reveal that the individual does not have any sleep or wake cycles. This results in a loss of consciousness (often referred to as a coma.) Depending on different factors and the severity of injury, an individual may remain in a coma, emerge from a coma, or experience an increased level of consciousness.