More Research Is Needed on the Dynamics of Neck Motion
You can't have a head without a neck ... more research is needed on how the neck moves and what impact those movements have on shearing within the brain during injury.
See more of Dr. Ghajar's videos here.
I think that we're far too much focused on the head. I think that people don't realize that the head is connected to the body or the neck. The neck is very flexible, and there are probably a lot of things going on in the neck that need to be studied in terms of its motion and its role in producing concussive deficits. Some studies have found that women have a higher instance of concussion than males do, and one theory could be that women have large brains, just like men, but they have smaller necks, and that the flexibility of the neck produces this shearing effect in the brain and produces concussion symptoms. I think this is something we need to look at. I think everyone is far too focused on helmets and focal impacts. I think we're totally missing the boat. We should be looking at the neck. I mean, if your neck was made of iron and didn't move, then fine, designing helmets with liners and airbags and so on is the right thing to do, but you've got a neck that's flexible, and you can just take this to NASCAR racers and Formula 1 racers. They use the HANS device, and as far as I can tell, the number of brain injuries since the HANS device has been around has dropped down dramatically. And now, of course, what they do is they have the helmet sort of stuck so that your head doesn't move very much, and you've got to do something where your head can move, but then at velocities where it could produce some shearing motion, you've got to put some kind of dampening on it. But we need to look more at the dynamics of the neck. That's what I'm trying to say. I think we've done a great job at focal injury to the head with helmets, and those are things that penetrate the head, skull fractures, scalp injuries and so on. But no helmet--my opinion is that no helmet will really prevent concussion no matter what you do to it as long as you have a neck. You need to look at the neck, and I think people who know about pathophysiology of traumatic brain injury and deal with the situation clinically know that the neck is very much involved in this, and we need to take a closer look scientifically about how we can dampen-- or at least for the beginning part, just look at what the neck dynamics are in relationship to head shearing motion.
Posted on BrainLine February 9, 2012.
Jamshid Ghajar, MD, PhD is chief of Neurosurgery at Jamaica Hospital-Cornell Trauma Center, clinical professor of Neurosurgery at Weill Cornell Medical College and president of the Brain Trauma Foundation.
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