Traumatic Brain Injuries – Concussions: What Are They?

It’s difficult to get through life without whacking your head on something. If you’re lucky, that little bump on your noggin results in nothing more than an “ouch!” and an expletive. Many times, what seemed like an insignificant bump results in a longer-term problem. Traumatic Brain Injury (or “TBI”) is a term that encompasses a variety of injuries to your brain. Some TBIs are obvious, but there are a vast number that go both undiagnosed and untreated. The most common of these is concussion.

We’ve all heard the term “concussion,” but what is it?  Here is what the Centers for Disease Control & Prevention (CDC) says:

A concussion is a type of traumatic brain injury—or TBI—caused by a bump, blow, or jolt to the head or by a hit to the body that causes the head and brain to move rapidly back and forth. This sudden movement can cause the brain to bounce around or twist in the skull, creating chemical changes in the brain and sometimes stretching and damaging brain cells.

There are essentially two types of forces that can result in a concussion:  contact and inertial.  When your head strikes an object (or an object strikes your head), both Contact and Inertial forces are at play. When your head accelerates rapidly (without striking an object), only Inertial forces are involved in concussion. Source: National Institute of Health.

What does that mean? While you can obviously have a concussion when your head makes sudden contact with an object, you don’t even have to hit your head to have a concussion. The simple sudden, rapid back and forth movement (acceleration) of your head alone can cause a concussion through the simple inertia of the movement.

How does this injury by “inertia” work? You have to think of your brain as soft tissue floating inside of your skull. The membranes and soft tissue that make up your brain and the tissue that holds your brain in place are pliable. They can move, unlike your skull, which will fracture, not bend. So, when your skull moves suddenly and rapidly, the acceleration of your skull can be so fast that the soft tissue inside doesn’t have time to move with it; when that happens, the bone of your skull actually strikes the that tissue and can cause your brain to “bounce” off the inside of your skull. As you can imagine, that’s not a good thing.

Here is a great video from the CDC of exactly how this mechanism of injury occurs: https://www.youtube.com/watch?v=Sno_0Jd8GuA

TBIs such as concussions are prevalent both nation and statewide. Nationally, about 50,000 individuals die each year. In Florida alone, there were 3,731 TBI deaths and 19,170 non-fatal TBI hospitalizations in 2013. A great many more TBIs like concussions occur every year. Many milder concussions go undiagnosed or untreated.

The take away? You do not have to hit your head to have a concussion. A simple whiplash type injury is enough to induce a concussion. Even “mild” concussions can cause serious injuries and symptoms. For these, the key is identifying the symptoms as concussion-related and seeking proper medical care.

With the recent focus on concussions brought on by the events surrounding many well-known NFL players, people are now realizing that concussions often go undiagnosed and untreated for a very long time, and additionally, that the long-term impact of multiple concussions on the brain can be devastating. The next time you knock your noggin against something hard, or your head gets whipped back and forth suddenly and rapidly, if you are feeling a little off afterwards, look for the signs of a concussion; you may have one.

This post is the first of a six-part series on TBIs and concussions. Stay tuned for the next installment: TRAUMATIC BRAIN INJURIES – IDENTIFYING THE SYMPTOMS OF CONCUSSION