I don’t know if you’re interested in this issue, but it would be informative to know how many of the current TBI cases were due to direct contact and how many were due to blasé wave effect alone. Also, we should know who among the groups were wearing which helmets with which pads inside. If you look carefully at blast wave brain injury, one sees that the blast wave itself causes the unprotected skull to ‘ripple’, resulting in bruising of underlying brain tissue. Even with a helmet in place, some blast wave energy penetrates the interior and generates at least some ‘tremble’ while the main ripple effect is generated on the helmet shell itself. As the helmet connects to the skull via helmet pads, a proper degree of ‘flex’ in the pads is necessary to prevent the helmet ripple from being passed through directly to the skull.
As Willie Moss of Lawrence Livermore NRL has shown, too firm helmet pads instantly harden from blast wave effect and can act as a direct transmitter of helmet ripple to the less-affected skull itself, leading to brain bruising and TBI.
Have a look at our website to see what our front-line troops are desperately trying to get the military to understand: their GI helmet pads are so hard and uncomfortable they remove their helmets at every opportunity, rendering their exposed skulls to blast wave injury even without direct contact. Even if helmets are worn, the ‘shrink-wrapped rocks’ …their term for their helmet pads…pass through the helmet shell ripple to the skull. A no-win situation that can easily be fixed if there were someone who gave a hoot and would buck the political stranglehold certain helmet pad manufacturers and Ability One have on procurement.
There’s gotta be a damn good reason over 95,000 of our precious resource in the military have gone outside the system and asked for our help to make their helmet pads more comfortable and more protecting from non-contact TBI due to blast wave injury without sacrificing significant protection. We do so gladly. Information as to how many go directly to manufacturers on their own is not available to us, but would be instructive as well.