What is Traumatic Brain Injury?

A traumatic brain injury happens when an outside force damages the brain, whether from a blow to the head in a car crash, a fall, a hit during a sports game, or a violent jolt that causes the brain to move inside the skull. 

According to the CDC, a TBI is damage caused by a bump, blow, jolt, or penetrating injury that disrupts normal brain function. What makes these injuries especially serious is that the initial impact is only part of the problem. 

In the hours and days that follow, the brain can continue to swell, bleed, or undergo chemical changes that cause additional harm, which is why a person who seems fine right after an accident can decline later, and why medical documentation matters just as much for treatment as it does for any legal claim that follows.

How Do Doctors Classify a Traumatic Brain Injury?

Doctors typically sort TBIs into three severity levels using the Glasgow Coma Scale (GCS), a 15-point test that measures alertness and responsiveness shortly after the injury, along with how long the person was unconscious and how long any memory gaps lasted.

These classifications capture the injury at a single point in time. Someone who looks mild at the scene can deteriorate quickly if bleeding or swelling develops, which is why continued medical observation after any head injury matters, even when the person seems okay at first.

Is a Concussion the Same as a Mild Traumatic Brain Injury?

Yes. A concussion is a type of mild traumatic brain injury, defined in the sports medicine literature as a complex process affecting the brain, caused by biomechanical forces that make the brain move or twist inside the skull.

You do not need to be knocked unconscious to have a concussion. Feeling dazed or confused, or having a gap in memory right before or after the impact, is enough. 

Common symptoms include headache, dizziness, nausea, sensitivity to light or noise, trouble concentrating, and irritability, and these symptoms can show up immediately or develop over hours or days.

Diagnosis relies heavily on symptoms and history rather than imaging, since most people with a concussion have a normal CT scan. 

A normal scan does not mean the injury isn’t real. Treatment typically starts with 24 to 48 hours of physical and cognitive rest, followed by a gradual, step-by-step return to normal activity, and most people recover within about six months, though some develop symptoms that persist longer and require specialized care.

What Happens Inside the Brain During These Injuries?

Understanding the mechanism helps explain why TBIs are unpredictable and why symptoms sometimes worsen before they improve.

• Direct impact injuries occur when the head strikes an object or is struck by one, often bruising the frontal and temporal lobes.

• Penetrating injuries happen when an object breaks through the skull and damages brain tissue directly, typically involving severe bleeding and requiring emergency surgery.

• Acceleration and deceleration forces, like whiplash, can injure the brain without any direct impact at all, stretching or tearing the nerve fibers that connect different brain regions in what’s known as diffuse axonal injury, which may not show up on initial imaging.

• Blast injuries from explosions can damage brain tissue and blood vessels through rapid pressure changes, without any visible external wound.

The initial mechanical damage can trigger secondary processes, including swelling, bleeding, disrupted brain chemistry, and inflammation, that continue for hours or days after the original injury.

What Are the Specific Types of Brain Injury?

Beyond the mild, moderate, and severe severity scale, doctors also classify a TBI by its structural type, which shapes both the treatment plan and what shows up on imaging. 

A peer-reviewed clinical reference published through the National Library of Medicine, classifies TBIs fall into two broad categories: closed head injuries, where the skull and the dura mater (the brain’s protective outer membrane) stay intact, and penetrating injuries, where an object breaches both. Closed head injury is by far the more common of the two and includes several distinct injury types:

• Concussion. The mildest and most common form of TBI, caused by the brain moving or twisting inside the skull. Mild TBI, including concussion, accounts for more than 90 percent of all TBI cases seen in hospitals.

• Contusion. A bruise on the brain tissue itself, most often affecting the frontal and temporal lobes, which sit closest to bony ridges inside the skull.

• Diffuse axonal injury. Widespread tearing or stretching of the nerve fibers that connect different brain regions, typically caused by rapid acceleration and deceleration, such as in a high-speed crash. This injury can be severe even when it doesn’t appear on an initial CT scan.

• Intracranial hematoma. Bleeding inside the skull, which is further broken down by where the blood collects: an epidural hematoma (between the skull and the dura), a subdural hematoma (between the dura and the brain surface, often from torn bridging veins), a subarachnoid hemorrhage (in the space surrounding the brain), and an intraparenchymal hemorrhage (bleeding within the brain tissue itself).

Penetrating injuries, where an object such as a bullet or piece of debris enters the skull and damages brain tissue directly, are less common but are considered the most lethal form of head trauma.

What Causes Most Traumatic Brain Injuries?

Falls are the leading cause of TBI overall, according to a CDC review, accounting for about 35 percent of TBIs in the general population and roughly 49 percent of TBI-related hospitalizations specifically (National Institutes of Health). 

The risk shifts heavily by age. Falls cause roughly 49 percent of TBI-related emergency department visits in children ages 0 to 17 and about 81 percent of TBI-related emergency visits in adults 65 and older, while falls account for 52 percent of TBI hospitalizations overall compared to 20 percent for motor vehicle crashes. Other leading causes include:

• Motor vehicle crashes, including cars, motorcycles, bicycles, and pedestrian strikes, responsible for about 17 to 25 percent of TBIs depending on severity

• Being struck by or against an object, a major cause in sports and workplace settings, accounting for roughly 16 percent of cases

• Assaults and violence, including gunshot wounds, accounting for about 10 percent of cases, with shaken baby syndrome a tragic cause of severe injury in infants

• Workplace accidents, including falling objects, equipment malfunctions, and falls from height in construction, warehouse, and manufacturing settings

Many TBIs result from someone else’s negligence, including unsafe property conditions, reckless driving, employer safety violations, ignored concussion protocols, or defective safety gear.

What Are the Symptoms of a Traumatic Brain Injury?

Symptoms fall into several categories, and early recognition matters.

Physical symptoms:

• Headaches, ranging from mild to severe

• Nausea and vomiting

• Dizziness or balance problems

• Blurred or double vision

• Sensitivity to light or noise

• Fatigue or disrupted sleep

Cognitive symptoms:

• Confusion or disorientation

• Short-term memory problems

• Difficulty concentrating

• Slowed thinking and processing speed

• Trouble planning or multitasking

Emotional and behavioral symptoms:

• Irritability and mood swings

• Anxiety and depression

• Impulsivity and poor judgment

• Personality changes that strain relationships

Emergency warning signs. Seek immediate medical care if you observe repeated vomiting, seizures, increasing confusion, a severe or worsening headache, weakness or numbness in the arms or legs, slurred speech, one pupil larger than the other, or a decline in consciousness. 

Some cognitive and emotional effects can be delayed by days or weeks, which is one reason medical observation after any head injury is worth taking seriously even when someone seems fine.

Can a Traumatic Brain Injury Cause Long-Term Problems?

Yes. TBI is increasingly recognized as a chronic condition rather than a one-time event. Long-term effects can include:

• Chronic headaches, sometimes developing into migraines, along with persistent dizziness, balance problems, and post-injury seizures

• Ongoing attention and memory problems, slower processing speed, and executive function difficulties with planning and problem-solving

• Depression, anxiety, post-traumatic stress symptoms, and lasting personality changes

• Difficulty returning to prior work or school, strained relationships, and in more severe cases, a lasting need for supervision or daily assistance

• In cases of repeated brain trauma, particularly in contact sports or military service, a degenerative condition called chronic traumatic encephalopathy (CTE), which can only be definitively diagnosed after death but is associated with memory loss, mood changes, and impulse control problems that worsen over time

There’s also a documented link between TBI and a higher risk of dementia later in life. A large population study published in The Lancet Psychiatry found that a history of TBI was associated with a 24 percent higher overall risk of dementia, with a single severe TBI raising the risk by 35 percent and a single mild TBI or concussion raising it by 17 percent (University of Washington School of Medicine). 

These long-term risks matter in legal cases because they represent ongoing losses that require compensation for lifetime care, lost earning capacity, and diminished quality of life, not just the bills from the initial hospital stay.

How Do Doctors Diagnose a Traumatic Brain Injury?

Diagnosis starts with the history of the incident, including the mechanism of injury, the speed involved in a crash, the height of a fall, and how long any loss of consciousness lasted. From there, doctors typically rely on:

• A neurological examination, including the Glasgow Coma Scale, pupil reactions, motor strength, coordination, reflexes, and mental status, often repeated to track changes over time

• Neuroimaging, usually a CT scan first in the emergency room to detect bleeding, fractures, or swelling, with MRI used for more subtle injuries like diffuse axonal injury

• Close observation, especially in the first 24 to 48 hours, since moderate and severe TBIs often require ICU-level monitoring

• Neuropsychological testing, which evaluates attention, memory, processing speed, and executive function to document cognitive effects and guide rehabilitation

There’s no single definitive test for a TBI, particularly a mild one. Diagnosis relies on combining the history, symptoms, exam findings, and test results, which is also why thorough documentation matters for any legal claim that follows.

What Does Treatment and Recovery Look Like?

Treatment depends on severity and changes as recovery progresses.

For moderate and severe TBI, acute care focuses on stabilization: maintaining breathing and circulation, controlling pressure inside the skull, and sometimes performing surgery to remove a blood clot or relieve pressure, while also working to prevent complications like infection, blood clots, or seizures.

For mild TBI, treatment has shifted away from prolonged rest toward a short period, typically 24 to 48 hours, of physical and cognitive rest followed by a gradual, activity-based return to normal life. Avoiding a second head injury during recovery is critical.

When symptoms persist, rehabilitation often becomes central to recovery, and can include:

• Physical therapy for balance, strength, and mobility

• Occupational therapy for daily living skills and strategies for returning to work or school

• Speech and language therapy for communication and cognitive-communication skills

• Neuropsychological rehabilitation, including cognitive exercises and compensatory strategies

• Psychological support to address mood changes and emotional adjustment

Recovery is rarely a straight line. Early gains can slow down, setbacks happen, and some people need years of therapy or lifelong support, which can involve significant costs for inpatient and outpatient care, home modifications, and assistive technology.

Can Traumatic Brain Injuries Be Prevented?

Many TBIs are preventable, which is part of why the law treats a negligent failure to prevent one so seriously. 

Common prevention measures include seatbelt use and proper child safety seats, helmets for motorcyclists and bicyclists, removing fall hazards and improving lighting at home.

Following concussion protocols in youth and adult sports, complying with workplace fall protection standards, and secure firearm storage. 

When a property owner, employer, school, sports organization, or manufacturer fails to take these basic precautions, that failure can amount to negligence.

When Does a Traumatic Brain Injury Involve Someone Else’s Negligence?

A TBI caused by another party’s carelessness can support a personal injury or medical malpractice claim. Common scenarios include:

• Car accidents, where a distracted, speeding, or impaired driver causes a collision

• Slip and fall or premises liability accidents, where a property owner failed to maintain safe conditions, such as an unaddressed spill, broken stair, or poor lighting

• Workplace accidents, such as a fall from height or a struck-by incident, which may support both a workers’ compensation claim and a separate personal injury claim against a negligent third party

• Sports injuries, where a coach, school, or organization ignored a known concussion protocol and allowed an athlete to return to play too soon

• Assault, where a brain injury results from an intentional act of violence

• Medical malpractice, including a delayed diagnosis of a brain bleed, a surgical or anesthesia error, or a birth injury caused by improper use of forceps or vacuum extraction

What Should You Know About New York’s Serious Injury Threshold?

If your TBI happened in a car accident, New York’s no-fault insurance system adds an extra step. 

Under Insurance Law § 5102(d), a car accident victim generally can’t sue the at-fault driver for pain and suffering unless the injury meets the “serious injury” threshold, since no-fault coverage otherwise caps recovery at $50,000 in basic economic loss. 

A traumatic brain injury, given its life-altering nature, will often qualify under categories like a permanent consequential limitation of a body function or a significant limitation of use, but it still has to be proven with objective medical evidence, including imaging and neuropsychological testing, not just self-reported symptoms. 

This is one of the reasons early, thorough documentation of a TBI matters so much in a New York car accident case.

Summing It Up

A traumatic brain injury ranges from a mild concussion to severe, life-threatening brain damage, and results from an outside force disrupting normal brain function, whether through direct impact, a penetrating wound, or the kind of acceleration and deceleration forces seen in a car crash. 

Effects can be immediate or delayed, temporary or permanent, and obvious or easy to miss, which is exactly what makes these cases so easy for an insurance company to undervalue.

Even a mild TBI can produce lasting problems with memory, mood, and daily functioning. When a TBI results from someone else’s negligence, whether a careless driver, an unsafe property, a preventable medical error, or an ignored concussion protocol, the resulting harm is real and, under New York law, compensable.

Porter Law Group builds brain injury cases the way a treating hospital would diagnose one.

If you or someone you love is dealing with a TBI caused by another party’s negligence, we can review what happened and explain what your options are..

Frequently Asked Questions

What is the difference between a concussion and a traumatic brain injury? 

A concussion is a type of traumatic brain injury, specifically the mild category. All concussions are TBIs, but not all TBIs are concussions. Moderate and severe TBIs involve longer loss of consciousness, longer memory gaps, and are far more likely to show visible damage on a CT or MRI scan.

Can a traumatic brain injury be mild and still be serious? 

Yes. “Mild” refers to the initial classification on the Glasgow Coma Scale, not the long-term impact. Research shows that about 10 to 20 percent of people with a mild TBI go on to develop persistent post-concussion symptoms lasting months or longer and even a single mild TBI has been linked to a 17 percent higher long-term risk of dementia.

Do you always lose consciousness with a traumatic brain injury? 

No. Many people with a TBI, including a concussion, never lose consciousness at all. Feeling dazed, confused, or having a gap in memory around the time of the injury is enough to indicate a brain injury, which is part of why TBIs are sometimes missed at the scene of an accident.

How soon after a head injury should you see a doctor? 

As soon as possible, and always immediately if you notice repeated vomiting, seizures, worsening confusion, slurred speech, or unequal pupils. Even without those signs, a same-day or next-day evaluation matters, since secondary swelling or bleeding can develop hours after the initial impact, and early documentation also matters if the injury may lead to a legal claim.

What is the most common cause of traumatic brain injury? 

Falls are the leading cause of TBI overall, followed by motor vehicle crashes and being struck by or against an object, according to CDC data. Falls are especially common among young children and adults over 65, while motor vehicle crashes are a leading cause of moderate and severe TBI across all age groups.

What is the difference between a closed head injury and a penetrating brain injury?

 A closed head injury means the skull and its protective outer membrane stay intact, even though the brain underneath can still be seriously hurt, through a concussion, a contusion, or bleeding inside the skull. A penetrating injury means an object actually breaches the skull and enters brain tissue, which is less common but is considered the most lethal form of head trauma. More than 90 percent of TBIs treated in U.S. hospitals are closed head injuries, and most of those are classified as mild.

Prior results do not guarantee a similar outcome.

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Email: info@porterlawteam.com