Why helmets don't protect our athletes

Picture: Joe Armao
Picture: Joe Armao

AFL footballer Paddy McCartin recently suffered his eighth concussion, leaving us to again consider what can be done to better protect players on the field.

Are helmets the answer? Indeed, cyclists as well as those involved in many other sports wear helmets. And for good reason, as helmets do protect the head — but only from serious skull and traumatic brain injury.

Logically, this means that helmets should protect against concussion, right? Well no.

Medical studies have repeatedly shown they do not protect the brain from concussion. Why?

It relates to the structure of the brain. Brain tissue is soft and takes little impact to distort ("squishy" is a word that comes to mind). Brains are not like what you may have dissected in high school, or see at a plastinated bodies exhibition.

The brain is so fragile that, in order to keep it safe, it is bathed in fluid separating contact with the skull bone. This fluid protects the brain from impacts, but only to a certain degree.

With heavy hits to the head, like those in contact sports, the fluid actually works against the brain. Big hits to the head cause stretching and shearing of brain cells because the fluid allows for movement.

But surely helmets protect the brain by reducing the impact of those big hits?

Depending on the material, some studies show reduction of impact, but not enough to stop the brain rapidly moving in its own fluid. This is still the problem.

I admit that debates about concussion are complicated. We see many retired players providing their thoughts, based upon their playing experiences, as to whether helmets may be effective.

These individuals have every right to express their personal opinion.

But in science we have to put our personal experiences and opinions aside, and that is not easy.

The science tells us (as uncomfortable as it may be) that currently there is no evidence that helmets protect against concussion.

However, science is a self-correcting practice.

If new technologies and materials developed can help redesign helmets to reduce trauma to the brain, and the scientific evidence is rigorously clear, helmets may one day play a role in protecting athletes.

Until then, I will defend the science that says helmets do not protect athletes from suffering concussion — irrespective of people's beliefs or personal experiences.

Dr Alan Pearce is a neuroscientist and associate professor at La Trobe University