Traumatic Brain Injury (TBI)

Head Injury

8 million/yr in US, 1.5 million serious, .5 million hospitalized, 100,000 die, 90,000 disabled, 2,000 end up vegetative

More Head Injury Stats:

l   2-3x more males than females

l   peak ages 18-24 & over 75

l   20% of those who die from head injuries don’t have a skull fracture; skull fracture is not a good predictor of outcomes  unless it is depressed

l   in 2/3 death results from excessive movement of the brain in skull

Causes of Head Injuries

l   50% in motor vehicle accidents

l   21% in falls

l   12% assaults & violence

l   10% in sports/recreational accidents

l   7% other

Sports Injuries

l   About 300,000 sport-related head injuries a year in US (9% serious)

l   Sports involved (from most frequent)

»  Equestrian

»  Boxing

»  Football, soccer, rugby

»  Bicycling

»  Martial arts; auto racing

»  Hockey


Types of Injuries

l   Concussion - transient neurologic dysfunction (altered consciousness or LOC) but no damage visible

l   Closed head injury (CHI)-skull intact; brain injured by excessive movement

l   Contusion - bruising of brain (surface blood vessels broken, tissue swells)

l   Penetrating injury or laceration - brain tissue torn or punctured (by bullet, bone fragment)


Focal Damage to Frontal Lobes

Floor of Skull

Coup-Contrecoup Injuries

Damage in CHIs

l   at point of impact (“coup”)

l   opposite point of impact (“contrecoup”)

l   where brain presses or is pulled against skull or dural partitions

l   where tissue is stretched, twisted or sheared -rapid deceleration causes diffuse axonal injury & petechia (pinpoint hemorrhages)

l   tissue compressed by intracranial pressure (blood, swelling) or fracture

Coup-Contrecoup Injuries

Increased Intracranial Pressure

l   No extra room in skull for blood, swelling

l   Increased intracranial pressure presses on brain causing symptoms, damage, and possible herniation

l   Signs: change in consciousness, pupils, breathing, motor function, headache, vomiting, seizures, personality, papilledema

Head Injury Related Bleeding

l   Epidural/extradural hematoma - most often after a blow to side of head damages meningeal arteries. May appear lucid after initial signs of concussion but then rapidly decline (1-2 hr) - drowsiness, hemiparalysis, 1 pupil may dilate.  Emergency surgery to relieve growing pressure before brain herniates.

Head Injury Related Bleeding (cont.)

l   Subdural hematoma - front/back blow causes slower bleed over days/wks

l   Intracerebral hematoma - bruising of brain can cause internal bleeding (most often frontal or temporal)


Epidural Hematoma

Subdural Hematoma

Craniotomy to Remove Hematoma

Herniation Due to Pressure

l   midline shift past falx cerebri

l   medial temporal lobe past tentorium, causing pressure on midbrain

l   cerebellum/medulla thru foramen magnum, causing pressure on medulla

l   herniation can quickly cause coma and death



Diffuse Axonal Injury

Petechial Hemorrhages

Gunshot Thru Brain

Basal or Basilar Skull Fracture

l   Sometimes visible surface of skull may be intact but injury has cause hairline fractures of the bottom of the skull

l   Fracture may tear dura or may injure the bones of the facial sinuses or auditory canal

l   Signs: Racoon’s eyes, Battle’s sign, otorrhea, rhinorrhea

Battle’s Sign



Possible Head Injury Sequelae

l   post-traumatic amnesia (PTA) or milder memory difficulties

l   focal losses (e.g cognitive, personality, motor etc.)

l   meningitis if head was opened

l   post-traumatic epilepsy

l   coma


Coma & Related States

l    Coma – total unconsciousness (eyes closed, can’t be aroused, no response to pain)

l    Persistant vegetative state – eye opening and periodic wakefulness, eye movements, grimaces, grasping/groping,withdrawal from pain, but no real awareness

l    Locked-in syndrome – consciousness but almost complete paralysis due to brainstem damage


l   wear seatbelts; use infant seats

l   avoid motorcycles; wear helmits

l   don’t drink excessively (& don’t drive)

l   beware of hazardous falls; use ladders appropriately

l   beware of assault situations; projectiles

CHIs Vary in Severity (see Iverson link)

l   Head Trauma with little or no injury

l   Uncomplicated Mild Head Injury

l   Complicated Mild Head Injury

l   Moderate Head Injury

l   Severe Head Injury

l   Catastrophic Head Injury