The American History of Wartime Head Injuries and Helmets, Part 7

“This Cougar in Al Anbar, Iraq, was hit by a directed charge IED approximately 300–500 lbs. in size.” Source: U.S. Military [Public domain], via Wikimedia Commons

The rise of the IED and TBI in Afghanistan and Iraq

 Though both the wars in Iraq and Afghanistan have featured conventional battles, they are largely asymmetric conflicts. Improvised Explosive Devices (IEDs), aka roadside bombs, started being deployed on a massive scale by insurgents in Iraq, but the tactic and the skills required to deploy them soon migrated through the international network of jihadists to Afghanistan and beyond.

IEDs quickly became the main cause of deaths and injury in both conflicts, spurring a cat and mouse game of tactics to deploy or defeat them by insurgents and Coalition Forces. The US rolled out better armored vehicles, such as the Mine-Resistant Ambush Protected (MRAP) vehicle, as well as various radio-frequency jammers to block radio-controlled bombs, for examples.

The US and its allies had some success: “At the start of the [Iraq] war in 2003, every device that troops encountered resulted in, on average, the injury or death of at least one member of the coalition forces; by 2009, insurgents had to put down nine IEDs to cause a single casualty.”

While the rates of injury have of course decreased after the US withdrawal from Iraq and a much lighter footprint in Afghanistan, “[s]omewhere between more than half to two-thirds of Americans killed or wounded in combat in the Iraq and Afghanistan wars have been victims of IEDs planted in the ground, in vehicles or buildings, or worn as suicide vests, or loaded into suicide vehicles, according to data from the Pentagon's Joint IED Defeat Organization or JIEDDO.” During the 2007 “Surge” in Iraq, IEDs “caused 70% of American casualties.”

And their use continues to be common in Afghanistan, as the Taliban and other insurgents rely on the bombs to fight an asymmetric war focused on destabilizing the government.

Closed head injuries: The “signature wound” of Iraq and Afghanistan

The widespread use of IEDs and access to better protective equipment that shields troops from other wounds have caused traumatic brain injuries to be declared “the signature wound” of the wars in Iraq and Afghanistan:

The effectiveness of body armor may contribute to a higher incidence of TBI in survivors because there is decreased mortality secondary to torso wounds. Many individuals who would have died in previous conflicts now survive; among those who do survive, a greater percentage have brain injuries. The use of Kevlar™ helmets has greatly reduced the incidence of penetrating head injuries from projectiles, but the brain remains susceptible to concussive forces. Furthermore, the increased use of improvised explosive devices (IEDs) as weapons has contributed significantly to the incidence of TBI.  

During the First Gulf War in 1991, about 20% of those treated for wounds had head injuries. In the current conflicts in Iraq and Afghanistan, blasts are the most common cause of wounds and the leading cause of TBI. Approximately two-thirds of army war zone medical evacuations are due to blast injury, and 88% of second echelon treatment site injuries are due to blast trauma.

While estimates vary, up to 400,000 service members may have suffered some sort of traumatic brain injury (TBI) during the two conflicts. Of those injuries, “approximately 80 percent of TBI diagnoses in the military are associated with closed head injuries incurred as a result of blasting or other activities not directly combat-related.”

A TBI can be caused by any physical strike that causes the brain to impact with the skull, but explosives have unique effects:

When a blast wave impacts the body, relatively high-frequency 'stress waves' and relatively low-frequency 'shear waves' are created. Stress waves result from rapid acceleration of the body surface. Shear waves are created by the magnitude of body-wall displacement and are generally perpendicular to stress waves and tangential to the body surface. Injury sustained as a result of the impact of the overpressurization wave is termed primary blast injury.

In addition to these blast wave forces, blast winds are also created in explosions. Blast winds move away from the epicenter of the explosions during the positive pressure phase of the blast, but quickly reverse and move back toward the epicenter during the negative pressurization phase of the blast wave. Blast winds can exceed hurricane force winds. These wind velocities can be magnified substantially by external conditions, e.g., by channeling through corridors or alleys.

Frustrating diagnosis and treatment are the facts that CAT scans and MRIs often can’t detect damage in milder concussions, and repeated injuries, especially in a short interval, result in even more significant damage; this can cause “repetitive head injury syndrome.” Whereas troops were quickly returned to frontline service after experiencing an IED strike earlier in the conflicts, the military eventually instituted procedures to remove “soldiers from combat if they have been in three blasts” as well as more effective monitoring for TBI.

The TCCC protocol for assessing TBI uses various metrics, including:

• Decreases in level of consciousness 

• Pupillary dilation 

• SBP [systolic blood pressure] should be >90 mmHg 

• O2 sat [oxygen saturation] > 90 

• Hypothermia 

• PCO2 [partial pressure of carbon dioxide; if this is too high, it indicates a toxic reaction] (If capnography is available, maintain between 35-40 mmHg)
• Penetrating head trauma (if present, administer antibiotics) 

• Assume a spinal (neck) injury until cleared. 


Diagnosis at higher levels of care includes a through neurological assessment and brain scans. Nevertheless, perhaps “tens of thousands troops” remain undiagnosed – and the long-term effects of TBI can include “headaches, balance problems, hearing problems, lack of self-control, mood changes, ringing in the ears, problems sleeping and memory loss.”

And, like earlier wars, many of the symptoms of a discernible, physical head injury are similar to post-traumatic stress, and the conditions are intertwined. Post-traumatic stress disorder (PTSD) can occur in the absence of a TBI, and a TBI can lead to an increased likelihood of experiencing post-traumatic stress.

“In one major study of 60,000 Iraq and Afghanistan veterans, 13.5% of deployed and nondeployed veterans screened positive for PTSD, while other studies show the rate to be as high as 20% to 30%.” 

Just as doctors in World War II attempted to distinguish the “neurologic/ “organic” (biomechanical) contributions from the psychological/ “psychoneurotic” contributions,” the modern medical community is struggling with the “perfect storm” of these factors:

When PTSD and TBI coexist, it’s often difficult to sort out what’s going on. Changes in cognition such as memory and concentration, depression, anxiety, insomnia, and fatigue are common with both diagnoses. One basically feeds and reinforces the other, so it’s a complicated mix — it’s the perfect storm. It may help to consider and compare changes commonly seen with TBI and PTSD.

Sufferers of both PTSD and TBI often cope with isolation, emotional lability (variability), sleep disturbances, fatigue, anxiety, substance abuse, and depression, but there are differences. Individuals with TBI more often cope with memory loss, for example, whereas PTSD sufferers often relive traumatic events and deal with hypervigilance, “a state of increased alertness.”

The military and the medical communities are attempting to grapple with the long-term health effects of TBI and PTSD in the wake of the conflicts in Iraq and Afghanistan. In 2016, the Army opened The Intrepid Spirit Center, “the fourth of its kind, but fifth to be officially dedicated,” an “$11 million, 25,000-square foot center” at Fort Bragg in North Carolina. The facility is a “a ‘one-stop shop’ for troops suffering from traumatic brain injury or PTSD at the nation's largest military installation.”

Robust research is also trying to increase understanding of the problem. In 2016, Dr. Magali Haas, the CEO of Cohen Veterans Bioscience, a “non-profit research organization with a singular focus on PTSD and TBI research,” wrote that scientific “papers on PTSD and TBI appeared last year at a rate of more than 10 a day. According to ClinicalTrials.gov, a registry of clinical trials run by the US National Library of Medicine, 117 trials are underway on PTSD and TBI and almost 400 more are currently recruiting participants.”

Nevertheless, the development of new treatments for PTSD remain slow, and the understanding of TBI and its interface with PTSD remains incomplete. Hass continued:

[Research leads] are not translating fast enough into diagnostic tools and treatments for service members and veterans. What is needed is a coordinated effort that brings together science and technology from the forefront of neuroscience, genetics, computer science, and medical imaging. Promising research from an array of fields must be scaled up and repeated to be sure that leads are worth pursuing into the costly and lengthy process of drug development. …

Eureka moments may make headlines, but real success is difficult to achieve without directed, sustained, unglamorous effort. The science community bears an obligation to make that effort for the service members and veterans who protect us.

To Be Continued: The American History of Wartime Head Injuries and Helmets

In the next blog in this series, Hard Head Veterans reviews the current and future of US ballistic helmets and armor systems.

Previous installments:

The American History of Wartime Head Injuries and Helmets, Part 1

The American History of Wartime Head Injuries and Helmets, Part 2

The American History of Wartime Head Injuries and Helmets, Part 3

The American History of Wartime Head Injuries and Helmets, Part 4

The American History of Wartime Head Injuries and Helmets, Part 5

The American History of Wartime Head Injuries and Helmets, Part 6