March is Brain Injury Awareness Month, so let’s close it out by dispelling 6 big concussion myths.
Before we start busting some myths, though, we first need to define CONCUSSION.
A concussion is a traumatic brain injury (TBI) caused by an external force either directly to the head or to the body and then transmitted to the head. It is classified as a mild TBI because there are no skull fractures or brain bleeds, but it’s hardly mild for the person experiencing it and it still needs to be taken seriously. 75% of all TBIs are classified as mild and in the vast majority of cases, the brain recovers completely within several days to a few weeks.
Ok, let’s get to mythbusting.
1. No blackout? No concussion
Loss of consciousness is not required for a concussion diagnosis. In fact, loss of consciousness (LOC) only occurs in 10% of concussions. Boom. Myth #1 busted.
2. Stay awake after a concussion
This myth is probably the most common, with the fear being that you may not wake up if you go to sleep after a concussion. Actually, sleep is one of the best antidotes after a concussion, as the brain needs adequate rest to resume optimal functioning. As long as the person is awake and can hold a conversation prior to sleeping, there is no need (and it’s actually detrimental) to deprive them of it.
3. Don’t exercise after a concussion
This gets a bit tricky. There’s a big difference between exiting the game/refraining from playing your sport after a concussion and resting your body completely. As described in a JAMA Neurology paper published this month, the initial goal was to remove an athlete from activities in which there is a high risk of sustaining another concussion. Preclinical studies suggested negative effects of early exercise on neuroplasticity, neurotrophins (proteins essential for neuronal function), and cognition. Clinical studies demonstrated worsening symptoms after forced exercise at acute timepoints post-injury. So where are we now? Return-to-play guidelines suggest voluntary exercise in a stepwise approach, as long as it does not exacerbate symptoms.
4. Helmets prevent concussions
If helmets prevent concussions, we probably wouldn’t have seen 281 (reported) concussions in the NFL’s 2017 regular season; an increase from the previous season. Current helmets are designed to mitigate skull fractures and brain bleeds (characteristic of more severe TBIs). With newer rating systems, however, we do see differences in helmet effectiveness; with some being more effective at preventing serious injury. Engineers are working on improving helmet design, but since concussions are caused by rapid acceleration and deceleration of the brain inside the skull, these external protective mechanisms must be very sophisticated. There is hope that new helmets, including the one recently adopted by the NFL, will greatly reduce the risk of a concussion, but it is unlikely that any helmet will completely prevent a concussion. In fact, there’s some concern that newer helmets will actually encourage a false sense of security, and concussion rates will rise.
5. Concussions cause CTE (chronic traumatic encephalopathy)
You’ve likely heard about CTE either in Will Smith’s movie, “Concussion”, or because of the NFL lawsuit. It’s a buzzword (buzz-acronym?) these days, but very few people outside of the Neurotrauma field know what it is. CTE is a neurodegenerative brain disease that has been correlated with repeated head trauma, particularly in former NFL players. However, correlation does not equal causation and it is important to remember that the vast majority of football players (and anyone who’s sustained repeat concussions) will not develop this disease. Many of the former players diagnosed with CTE were playing during a time when the league was in denial about the concussion problem. This was also a time with almost nothing in the way of concussion protocol; players were staying in the game after sustaining a concussion, which lead to repeat concussions before the brain had a chance to recover for the initial insult. All these factors likely contributed to more severe consequences in at-risk (keyword: at-risk) brains. Stay tuned for a full post on this topic this summer, before we head in to football season.
6. A new blood test can detect a concussion
In February, the headiline “FDA approves first blood test for concussion” splashed across major media outlets. Unfortunately, these headlines were a bit misleading. The FDA did approve a blood test that can detect intracranial lesions (brain bleeds) after a TBI. However, this result alone cannot confirm or rule out a concussion. Instead, this test was initially developed to help doctors decide whether or not to order a CT scan, which is grossly overused. As a side note, this blood test detects levels of GFAP and UCH-L1, two proteins that are elevated for up to 12 hours after brain trauma. The quest for biomarkers after concussion has been elusive thus far. It is likely that a concussion can only be biochemically diagnosed based on a pattern or profile of many protein changes, rather than just one or two. Furthermore, while the blood test can be performed within 20 minutes of a concussion, the results can take up to 3 hours, rendering it useless for sideline diagnoses. But, it is a step in the right direction and may eventually become a great supplemental tool.
And now you know.