Concussion Risk in Children & How to Minimize It
Concussions are functional injuries that result from the sudden acceleration or deceleration of the head, neck or body. While they can occur in people of all ages, children are particularly susceptible to concussions and their recoveries can be complicated. Here is why:
The Brain is Still Growing
The first five years of life is when your brain experiences 90% of its growth in terms of size. During this time, young brains are creating massive amounts of new synaptic connections; literally every single minute. It is due to this rapid expansion that the developing brain is more vulnerable to injury.
Myelin is a specific type of fat molecule that lines the long tubular cells, or axons, that are located deep within the white matter of the brain. In fact, the reason why it is termed ‘white matter’ is because of this fat wrapping, that appears white in colour.
Myelin sheaths wrapping each of the cell tracks help the signals within our nervous system to transmit at a faster rate. If a signal was to go along a “naked” or unwrapped neuron, it would go at a slower pace. Myelination allows the signal to jump between segments of the nerve so the message can travel much, much faster.
In addition to faster signal transmission, myelin also protects the brain, with the fat acting as an insulating layer for the brain cells. However, the process of myelination is generally not complete until between the ages of 15 and 17. This means that younger children, under the age of 15, have the potential to be concussed with less force, due to their brains exhibiting an incomplete insulation layer.
Blood / Brain Barrier
Something else that is developing right along with the brain in young people is the blood / brain barrier. This membrane is responsible for keeping dangerous toxins and pathogens out of the brain.
Children are far more susceptible to blood / brain barrier damage when they receive a concussion. When this membrane becomes leaky and begins to allow things into the brain that shouldn’t be there, the brain can become inflamed, and the child can experience mild to severe cognitive impairment.
Head to Body Ratio
One of the ways in which the risk of concussion can be reduced is through neck stiffness. From a biomechanical perspective, if you were to get hit in the head, but your neck was completely rigid, not a movable, pliable structure, there would be far less chance for a sudden acceleration of the brain.
Also from a developmental biomechanical perspective, children are a bit like bobblehead dolls. They have these giant heads on tiny, underdeveloped necks and bodies. By the age of 4, a child’s head is 90% fully grown, but their body is only 19% of their full body weight. By age 12, the head is 95% fully grown, and the body still hasn’t caught up, being only 50% grown at this point.
So, in summary, children have these big, heavy heads on tiny little frames, which makes them more susceptible to any type of impact.
Less G Force Needed
The mean peak linear force required to sustain a concussion, in terms of acceleration in high school and collegiate athletes, is approximately 100 G’s – with the full range being between 70 and 120.
There have only been a couple of biomechanical studies completed in children. So far, studies have shown that the mean peak linear force for children, where the average age is 11 years old, is roughly only 60 G’s . With a range between 30 and 90 G’s of force.
Are kids more susceptible to getting concussed with less force because they have lower myelination, a smaller head-to-neck ratio, or a more porous blood / brain barrier? We’re not really sure, though it’s most likely a combination of all of the above factors.
A Lack of Self-Awareness
Now, to make things more difficult, children don’t have the same level of self-awareness as adults (if you’re a clinician who works with kids you’ll understand this concept). They also have a limited vocabulary. This combination makes it difficult for them to recognize their own symptoms or that something is potentially not right, and subsequently for clinicians to properly diagnose and treat children.
Cognitive Impairments: Correlation VS Causation
There is some evidence that concussions early in life can lead to longer standing cognitive impairments, learning disabilities and more once children reach middle school and high school. Now, we must be careful with this because correlation and causation are two very different things, and can often be misconstrued.
Generally, when people outside of scientific circles talk about the association between two things, people tend to infer that “thing A” caused “thing B,” but that is not necessarily the case. There are certainly times when “thing B” causes “thing A” or when two things are simply related or associated in some way.
We have some evidence that children who sustain concussions tend to have impaired cognitive performance in middle school and high school. But the next question is, what are the other variables involved?
You might have someone with a learning disability, and with enough studies, we may find that those adolescents with learning disabilities have more of a risk of sustaining a concussion because of their choices and behavior.
So, we can’t necessarily say that the concussion caused a learning disability, because it could be the other way around.
A classic example of this is the association between concussion and ADHD. For the longest time, it was thought that concussion increased your likelihood of developing ADHD.
Studies are now starting to emerge looking at the timing of ADHD diagnosis, and they’re finding that majority of the time a diagnosis of ADHD actually precedes the first concussion. This suggests that concussion is not a risk factor for developing ADHD, but rather ADHD is a risk factor for sustaining a concussion.
Recently, Gunn and colleagues published a study examining concussion risk in collegiate athletes with ADHD, learning disabilities, or both learning disabilities and ADHD. They found “… neurodevelopmental disorders may be associated with increased odds of single and multiple concussions irrespective of sex.” 
While we must be careful with correlational studies, it’s plausible to say that concussion in early childhood could have some long-lasting cognitive impacts.
Reducing Concussions in Children
Children can be concussed with less force, their developing brains don’t have the same level of myelin insulation as older adults, they have a more vulnerable blood / brain barrier, a poor head-to-neck ratio, and an inability to confidently verbalize when they are, in fact, experiencing concussion symptoms.
It goes without saying that we should be working toward eliminating – or at least significantly reducing – concussions in children. Particularly before the age of 15!
But how, exactly, do we do this?
Is it to outfit our children with better protective gear? Nope, none of it works. A helmet is great to reduce the risk of a skull fracture, but it isn’t going to stop a concussion from occurring.
A concussion is the result of a sudden acceleration of the head, neck or body, usually brought about by a collision of some sort. So, how do we reduce the risk of these collisions?
Body Checking: Not a Great Idea for Kids
Carolyn Emery, a research clinician in Alberta, has done a lot of work in concussion safety. She and her team found a few years ago that when body checking was removed from peewee hockey (ages 11 – 12), they saw a significant drop in the incidence of concussion. The same thing was found when they removed body checking in bantam hockey (ages 13 – 14).
Similarly, there’s a big push right now in the United States from the Concussion Legacy Foundation to ban tackle football until the age of 14. Prior to this age, children would play flag football, thereby reducing collisions and the risk of sustaining a concussion.
Reduce Contact in Practices
There are some sports organizations that are adamantly against removing contact from the game. In these cases, we would urge them to at least remove or significantly reduce the amount of contact that occurs in practice. By reducing the amount of time given to full contact drills, you are reducing the number of potential hits that a player takes during practice.
Practices don’t have the big hits like games do for obvious reasons. But there was a study done by Breton that looked at drill-specific head impact biomechanics. They found that if you reduced contact drills in football by as little as 15 minutes per practice, it would reduce the number of hits an average college athlete would get over a four-year football career by over 1000 . That’s 1000 less hits to the head over a four-year college football career just by reducing contact practice drills by 15 minutes.
The bottom line is, the only real way to reduce the risk of concussion is to reduce the risk of contact. It’s really the only way we can protect young children from concussion.
Concussion Management is Also Key
Regardless of the rules or preventative measures in place, concussions are still going to happen. The next best thing you can do is to ensure you have a good management strategy in place.
After concussion, we know that the brain is vulnerable. This is particularly true in children. Young children are far more apt to experience what is called second impact syndrome. That is when a person gets a second concussion before they have fully recovered from the first. In rare cases, this can be fatal.
We know that after a concussion there is a significant drop in brain energy levels. If the child gets concussed again, when their brain energy levels are low, those levels may drop even further, potentially to the point of causing death, permanent damage, or, at the very least, a prolonged recovery.
Do NOT Rely on Symptoms
Symptoms are never a good indicator of where in the healing journey a person may be. For instance, if you break your arm, the doctor puts a cast on it for 6 weeks to allow your bone to heal. Roughly 10 days after the initial break, your arm will start feeling better. Now your symptom of “pain” has greatly diminished. Do you cut the cast off and decide to go play a game of pick-up basketball? Of course not. Because you know even though the pain has subsided, the bone is still fragile and needs more time to heal. If you tried to play with a broken arm, you’d risk further damage, or sustaining another nasty injury.
We need to think of concussions in the same way. Many injured athletes think they can go back to their sport after a few days because their initial headaches – or whatever their presenting symptoms were – have gone away. But symptoms don’t matter because ultimately the underlying injury is still present.
Now with a broken arm, you can get an x-ray that will show that your bone is still broken even though it feels better. But a concussion doesn’t show up on an x-ray and it doesn’t show up with an MRI. A concussion is a functional injury and the only way we can determine when an athlete is healed and ready to get back into the game is to determine how their brain is functioning.
When we determine brain function, we assess things like reaction time, visual tracking, concentration, memory, and balance. These help us know when it’s safe to send you back out onto the field or ice. But we need something to compare your post-concussion testing.
Yearly Baseline Testing
It’s crucial that athletes in high risk sport get a yearly baseline test. Now with young children, it’s not enough to give them a regular computer test (neurocognitive test). These baselines are actually not validated for children under the age of 12. In addition, computer tests miss important additional functions like ocular motor tracking and balance.
We recommend parents and coaches ensure their young children / players work with a good multi-modal baseline assessment each year so that in the event of an injury, you have something to work from. We also recommend working with a clinician or specialists that are experts in testing and managing concussions.
Children are far more susceptible to sustaining a concussion for a multitude of reasons. From a developing brain to less myelin protection, a poor head-to-body ratio and lack of solid verbal skills, children are at a heightened risk.
To mitigate this risk, sports organizations should work to reduce the amount of contact, both in the game and in practices. And, in addition, solid concussion management strategies should be put into place, including having the right testing done each and every year.
If you need help with concussion management and prevention strategies, please reach out to us. Complete Concussion Management works with clinicians, parents and sports clubs around the world. We specialize in concussion testing, concussion rehab, return to school, and return to sport. We’ve worked with thousands and thousands of athletes of all ages and can help you keep your children as safe and healthy as possible.