This article appeared in The Year in Veterans Affairs & Military Medicine, 2005-2006 Edition, published by Faircount Media Group. (Click here to see a pdf of this article.)

The term “IED” has found its way into common parlance as the war in Iraq and Afghanistan continues. It stands for “improvised explosive device.” While the word “improvised” seems to suggest a thrown-together, homemade bomb that might or might not work, the reality is much more terrifying. At least one IED produced enough deadly force to lift and flip a 25-ton armored vehicle off a roadway, killing the 14 Marines inside. Others turn cars into bombs that explode on street corners, killing or injuring civilians and military personnel who happen to be nearby. Others strapped to people become living bombs. IEDs have become the signature weapon of the insurgents. And one of the injuries they cause is becoming the Iraq war’s signature injury: traumatic brain injury, or TBI.

Traumatic brain injuries are caused by external force and can result from many things: vehicle accidents, getting whacked on the head too hard during a football game or a boxing match, falls, domestic or street violence, gunshots, shaken baby syndrome. In the United States, according to the National Institutes of Health, TBI is “a disorder of major public health significance,” striking more than 1.5 million people every year, with currently more than 5 million suffering permanent and damaging disabilities. And with this war, it appears that larger than usual numbers of military personnel are sustaining TBIs. This is due in large part to IEDs, although bullets, land mines, and rocket-propelled grenades are doing much damage as well. In fact, all these devices are responsible for 70 percent of injuries in Iraq and Afghanistan.

Some TBIs come from wounds that penetrate the skull and the brain. These “open head” wounds are obvious and often horrendous. But others come from “closed head” injuries that can be invisible even to the most sophisticated neuro-imaging machines. A blow to the head that doesn’t even bruise the skin can cause one of these, and so can an explosion’s “concussive impact,” something against which helmets offer no protection.

Here’s why:  The brain is the consistency of Jell-O, and it floats within the hard skull. When a powerful explosion’s blast wave—a shock wave of highly pressurized air followed by a blast wind of incredible force—collides with a human body, that body accelerates uncontrollably. And even if the head does not hit anything, the brain, which  at first accelerates along with the head, instantly decelerates as it slams into the skull, and then it rebounds or, even deadlier, it twists. The area through which the blast wave travels can also play a role: In an open space, the damage to nearby humans may be less than if the blast wave ricochets off walls or other large obstacles, flinging the delicate brain in several directions before it subsides. All this violent activity can shear off or kill neural structures (and damage other internal organs), as well as cause brain bleeding and swelling. This can leave the victim with mild to severe brain damage and with
a life that may be horribly and irreversibly altered.

Concussive impact is being called modern warfare’s growing threat. And right now, it’s impossible to defend against.

A Disquieting Trend
Head wounds and brain injuries have always been a part of war. Floyd “Shad” Meshad, psychiatric social worker, traumatologist, and president and  founder of the National Veterans Foundation, sustained a mild TBI in a  helicopter crash in Vietnam. “There were a lot of head wounds in Vietnam,” he says. “Most of the GIs took off their helmets and flak jackets. It was 120 degrees and 100 percent humidity. And we didn’t wear our helmets much in combat.”

It’s impossible to know how many soldiers in Vietnam and earlier wars sustained traumatic brain injuries, although it’s been estimated that 20 percent of survivors did. In the current war, that percentage appears to be higher.

Beginning in January 2003, Walter Reed Army Medical Center in Washington, D.C., began studying a “a very select group of patients injured by a mechanism known to be high-risk for TBI,” says Dr. Warren Lux, neurologist at the Defense and Veterans Brain Injury Center (DVBIC), headquartered at Walter Reed. He says that among these warfighters with severe injuries from a blast, motor vehicle accident, fall, or gunshot wound to the head, face, or neck, 50 to 60 percent sustained a TBI, with a little more than half of those being moderate to severe. (See “What TBI Does,” below.) When that select group is counted within the 1,116 patients treated there for all battle injuries through April 2005, the percentage with TBI is 31 percent. It’s also possible, he says, that a few more had mild TBI that went unscreened.

Is this percentage really higher than in earlier wars? Lux cautions that no one really knows yet if that is true. Brain injury “has gotten more attention in this war,” he says. Articles about brain-injured soldiers have appeared in publications from the New England Journal of Medicine to People to local newspapers. Additionally, general advances

BACK TO Archives