Is a concussion a traumatic brain injury (TBI) or a mild brain injury?
By: Sarah Schulz / BHSc, MScOT, OT Reg (Ont.)
Concussion vs Traumatic Brain Injury (TBI) - What is the difference?
Normally, people use the term concussion when they assume that an individual’s symptoms will be cured in a few days or weeks. This may not be true however, because everyone’s symptoms may vary, and there is no solid way to predict how someone will recover. The word traumatic brain injury immediately instills a thought that an injury is extremely severe and disabling, so we tend to say someone has a concussion rather than a TBI.
This confusion leads to stigma around concussion and TBI, often leading to false assumptions.
So together let’s break down these terms:
Brain injury in general is defined as: an insult to the brain which results in changes in the brains function. It is broken down into 2 types of injuries:
1. Traumatic brain injury (TBI): which is defined as alteration of the brain caused by an external force (such as a blow to the head, fall)
2. Acquired brain injury (ABI): which is defined as a non-traumatic brain injury due to internal factors (such as stroke, aneurysm, tumor)
How does a traumatic brain injury (TBI) occur?
There are several ways in which the brain can be injured:
1. Direct hit (contusion): this is when there is a direct hit to the skull which causes the brain to be injured on impact
2. Coup-counter coup: this injury occurs when there are contusions on the brain on the direct site of impact, and on the complete opposite side (due to the head moving after the initial impact)
3. Diffuse axonal: this can occur from shaking or strong rotation of the head. There actually does not need to be any impact on the head, the brain moving in the skull causes damage
4. Penetration: occurs from impact of an object into the brain
- The key point here: NOT ALL TBI’S OCCUR FROM DIRECT IMPACT!! You can have an injury without hitting your head!
What are the leading causes of brain injuries?
Falls
Motor vehicle accident
Sports-related
Categories of Traumatic Brain Injury
There are a lot of factors determining what category an individual will be placed in when they experience a TBI. There are 3 levels (mild, moderate and severe) and they are defined based on different criteria.
Mild TBI:
o There may or may not be loss of consciousness, but it is very brief (seconds or minutes)
o Testing and scans may appear normal
o A change in mental status occurs and/or confusion/dazed at time of injury
Moderate TBI
o Loss of consciousness from a few minutes to hours
o Confusion lasts for days/weeks
o Impairments last for months or are permanent
Severe TBI
o Loss of consciousness for days
o Severe, permanent impairments brain function
What is a Concussion?
Now if you read the mild/moderate TBI definition and thought to yourself “that sounds a lot like what a concussion is”, you’re right! Concussions fall under the traumatic brain injury category, which is where the confusion begins. There is no actual agreed upon definition of a concussion due to the fact there is no real difference between what defines a TBI and what defines a concussion. Researchers have invested a great deal of time into defining concussion separate from TBI. However the consensus is that concussion falls under the mild/moderate TBI category. So, when you say someone has a concussion, you are actually saying they have a mild to moderate traumatic brain injury!
Mild vs Moderate TBI
The reason why concussion can fall into both mild AND moderate TBI is due to how symptoms heal. Brain injuries can take anywhere to heal from days, to weeks, to months. Some people still have symptoms later in life, and this is where we begin to call the injury a moderate TBI. Generally, what separates a mild TBI from a moderate TBI is how long the person takes to recover fully, and if they have any symptoms that stay with them.
Concussions, as I’ve mentioned, typically are assumed to be just mild brain injuries. But these injuries can continue and impact someone later in their life and are much more serious than people think.
Mild/moderate TBI’s are usually non-life threatening but can still have serious impact on a person's functioning. The assumption that a mild TBI is not serious is false. All brain injuries can impact someone’s ability to do the things they want, need and have to do in their life.
We hope that this information is helpful to you in learning more about the vocabulary that is often used when discussing brain injury. We recognize that this distinction can sometimes feel like it diminishes the not so mild impacts that a concussion can have on someone’s life.
Stay tuned for our next blog post where Felicia and Allie provide their insights on the impacts of labelling concussions as mild brain injuries.
References
Brain Injury Alliance of Utah. (n.d.). Types and Levels of Brain Injury. Retrieved from
https://biau.org/types-and-levels-of-brain-injury/Centre
for Disease Control and Prevention. (n.d). Concussion and Traumatic Brain Injury.
Retrieved from https://www.cdc.gov/traumaticbraininjury/get_the_facts.html
Public Health Agency of Canada. (2020). Injury in review, 2020 edition: Spotlight on traumatic
brain injuries across the life course. Retrieved from https://www.canada.ca/en/public-
health/services/injury-prevention/canadian-hospitals-injury-reporting-prevention-
program/injury-reports/2020-spotlight-traumatic-brain-injuries-life-course.html
Rao, D., McFaull, S., Thompson, W., & Jayaraman, G. (2018). At-a-glance – Traumatic brain injury management in Canada: Changing patterns of care. Public Health Agency of
Canada, 38(3), 147-150.
