Traumatic brain injuries are not all the same. The type, location, and mechanism of injury determine symptoms, treatment options, and long-term outcomes. Understanding the different types of TBI helps victims and families grasp what they're facing—and helps attorneys build compelling cases that explain the injury's impact.

Classification by Mechanism

Closed Head Injuries

In a closed head injury, the skull remains intact while the brain is damaged by impact or movement. These are the most common TBIs and include:

  • Concussions from falls or collisions
  • Acceleration-deceleration injuries from car crashes
  • Blast injuries from explosions

Closed head injuries can be deceptively serious—the absence of visible skull damage doesn't indicate the brain is unharmed.

Penetrating Injuries

Penetrating injuries occur when objects breach the skull and enter brain tissue:

  • Gunshot wounds
  • Stab wounds
  • Shrapnel from explosions
  • Objects propelled in industrial accidents

Penetrating injuries cause localized damage along the wound track plus potential widespread effects from bleeding and swelling.

Types of Brain Injuries

Concussion

A concussion is a mild TBI caused by a blow or jolt that makes the brain move rapidly within the skull. Despite being classified as "mild," concussions can cause significant symptoms:

  • Headaches and dizziness
  • Confusion and memory problems
  • Nausea and balance issues
  • Light and noise sensitivity
  • Sleep disturbances

Most concussions resolve within weeks, but up to 15-30% of concussion sufferers develop persistent symptoms lasting months or years.

Contusion

A contusion is a bruise on the brain itself—bleeding and swelling in brain tissue. Contusions occur at the impact site and sometimes on the opposite side of the brain (coup-contrecoup injury) where the brain rebounds against the skull.

Large contusions may require surgical intervention to relieve pressure.

Diffuse Axonal Injury (DAI)

Diffuse axonal injury is among the most serious TBIs. Rapid acceleration-deceleration forces cause widespread tearing of nerve fibers (axons) throughout the brain.

DAI characteristics:

  • Often caused by high-speed vehicle crashes
  • May not appear on CT scans initially
  • Causes widespread dysfunction rather than localized damage
  • Often results in coma or severe disability
  • Carries poor prognosis for recovery

Intracranial Hemorrhage

Bleeding within or around the brain creates dangerous pressure. Types include:

Epidural hematoma – Bleeding between the skull and the brain's outer covering (dura). Often caused by skull fractures tearing arteries. Medical emergency requiring immediate surgery.

Subdural hematoma – Bleeding between the dura and brain surface. Can be acute (immediately dangerous) or chronic (developing slowly over weeks). Common in elderly patients after falls.

Subarachnoid hemorrhage – Bleeding in the space surrounding the brain. Causes severe headaches and can lead to stroke-like complications.

Intracerebral hemorrhage – Bleeding within brain tissue itself, causing direct damage to brain cells.

Skull Fractures

While not brain injuries themselves, skull fractures often accompany TBI:

  • Linear fractures – Simple cracks that may heal without treatment
  • Depressed fractures – Bone pushed inward, potentially damaging brain tissue
  • Basilar fractures – Fractures at the skull base, risking infection and nerve damage
  • Open fractures – Skull broken with skin laceration, creating infection risk

Secondary Brain Injuries

The initial trauma often triggers secondary injuries that compound damage:

  • Cerebral edema – Brain swelling that increases pressure
  • Ischemia – Reduced blood flow starving brain cells of oxygen
  • Hypoxia – Insufficient oxygen reaching brain tissue
  • Increased intracranial pressure – Dangerous buildup requiring intervention
  • Infection – Particularly with penetrating injuries or skull fractures

Preventing and treating secondary injuries is critical to outcomes—negligent medical care that fails to manage these complications can constitute malpractice.

Injury Location and Function

Where the brain is damaged affects which functions are impaired:

Frontal Lobe

  • Personality and behavior changes
  • Impaired judgment and decision-making
  • Motor function problems
  • Speech difficulties (expressive)

Temporal Lobe

  • Memory problems
  • Language comprehension difficulties
  • Emotional instability
  • Hearing and auditory processing issues

Parietal Lobe

  • Sensory processing problems
  • Spatial awareness deficits
  • Difficulty with reading and math
  • Coordination issues

Occipital Lobe

  • Vision problems
  • Visual processing deficits
  • Difficulty recognizing objects or faces

Cerebellum

  • Balance and coordination problems
  • Tremors and motor control issues
  • Dizziness

Brain Stem

  • Consciousness and arousal problems
  • Breathing and heart rate regulation
  • Sleep-wake cycle disruption
  • Basic life functions

Legal Significance of TBI Types

Understanding TBI types matters for litigation:

  • Diagnosis documentation – Specific injury types require specific diagnostic evidence
  • Causation – Different injuries result from different mechanisms, linking to accident facts
  • Prognosis – Injury type affects expected recovery and future damages
  • Treatment needs – Different injuries require different (and differently costly) treatments

Conclusion

Traumatic brain injuries encompass a wide spectrum of conditions with varying symptoms, treatments, and outcomes. Proper diagnosis and classification of TBI type is essential for appropriate treatment and accurate legal claims. An experienced TBI attorney ensures that medical evidence properly documents the specific brain injury and its full impact on the victim's life.