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Identifying and Treating Concussion/mTBI in Service Members and Veterans
A Course for Civilian Health Care Providers from BrainLineMilitary.org
Many thousands of men and women in the U.S. military have sustained concussions (also called mild traumatic brain injuries, or mTBIs) while serving in Iraq and Afghanistan. In fact, traumatic brain injury has been called one of the signature injuries of these wars.
Some of these service members may present to your office with symptoms such as headaches or insomnia. Unless you know that your patient has been in combat and you ask the appropriate questions, it would be easy to overlook concussion/mTBI as an underlying cause.
Whether you are a doctor, physician assistant, nurse, physical therapist, social worker, or any other kind of civilian health care provider, knowing if your patient has been in combat can help you provide more effective treatment.
What Is a Traumatic Brain Injury (TBI)?
In order to understand concussion/mild TBI, it is important to first understand the general characteristics of traumatic brain injury or TBI. The Department of Defense and the Department of Veteran Affairs define a TBI as follows:
A traumatically induced structural injury and/or physiological disruption of brain function as a result of an external force that is indicated by new onset or worsening of at least one of the following clinical signs, immediately following the event:
- Any period of loss of or a decreased level of consciousness (LOC)
- Any loss of memory for events immediately before or after the injury (post-traumatic amnesia or PTA)
- Any alteration in mental state at the time of the injury (confusion, disorientation, slowed thinking, etc.) (Alteration of consciousness/mental state or AOC)
- Neurological deficits (weakness, loss of balance, change in vision, paresis/plegia, sensory loss, aphasia, etc.) that may or may not be transient
- Intracranial lesion
External forces may include any of the following events:
- the head being struck by an object
- the head striking an object
- the brain undergoing an acceleration/deceleration movement without direct external trauma to the head
- a foreign body penetrating the brain
- forces generated from events such as a blast or explosion
- or other forces yet to be defined
Not all individuals exposed to an external force will sustain a TBI, but any person who has experienced such an event and immediately showed the above signs and symptoms likely has had a TBI.
What Is a Concussion/mTBI?
As noted before, a concussion is synonymous with a mild traumatic brain injury (mTBI). Concussions can result from a collision of the head with an object, a pressure wave from a blast that passes through the head, or simply from sudden acceleration or deceleration of the head without impact. A service member or veteran may be diagnosed with a concussion/mTBI when such blows or jolts to the head are immediately followed by:
- A change in mental status of at least one of the following durations:
a. loss of consciousness for no more than 30 minutes
b. altered consciousness (mental confusion) for no more than 24 hours
c. an inability to remember events that lasts no more than 24 hours (post-traumatic amnesia)
- Normal results on standard neuroimaging
- Highest Glasgow Coma Scale (GCS) score within 24 hours between 13 to 15
You have probably encountered concussions in your practice with patients who have been in automobile crashes or taken a hit on the football field. Military service members certainly can receive concussions by these same mechanisms.
But the most common cause of concussion/mTBI among service members who deployed to Iraq and Afghanistan is a blast from an improvised explosive device (IED). A blast can result in a TBI even when the head does not collide with an object. Blast can affect the entire body, injuring limbs, eyes, and ears, for example.
Blast injuries are divided into four classes:
- Primary blast injuries are caused by the blast's shock wave traveling through the body.
- Secondary blast injuries are caused by shrapnel and other flying debris hitting the body.
- Tertiary blast injuries occur when the service member is accelerated into a solid object such as the ground or the interior of a vehicle.
- Quaternary injuries include crush injuries, burns, and inhalation of smoke or noxious gases.
Watch this slideshow on blast injuries to the brain:
"Since 2006, blasts have been the most common cause of injury among American soldiers treated at Walter Reed Army Hospital "
Blast Injury A Personal Account
Watch this video segment from Capt. J.L. Hancock, who sustained a concussion/mTBI in Afghanistan:
VIDEO: TBI in Theater
TBI in Theater
Blast waves are the primary cause of brain injury in theater; and they can be complicated by falls or crashes in military vehicles or by being thrown against a vehicle wall or building.
More than 233,000 service members sustained a TBI between 2000 and 2011, of which more than three-quarters were categorized as mild.
These statistics include service members injured on the battlefield ("in theater") and in non-combat settings and is a good reminder that asking about a history of concussion/mTBI should not be limited only to a service member's deployment experiences.
Moderate and severe TBIs, including penetrating cranial injuries, are usually diagnosed at the time of injury; their diagnosis requires a period of unconsciousness of more than 30 minutes and post-traumatic amnesia that lasts longer than a day. What you are most likely to encounter in your civilian practice is concussion/mTBI.
Diffuse Axonal Injury
The trauma that causes a concussion/mTBI can injure the brain's neurons in a variety of ways that are not easily identified using standard neuroimaging techniques. One kind of damage is called diffuse axonal injury (DAI), in which axons (the output fibers of neurons) are twisted, stretched, or severed.
Watch this video from Georgia Health Sciences University illustrating diffuse axonal injury:
VIDEO: Understanding Diffuse Axonal Injury
Understanding Diffuse Axonal Injury
Diffuse axonal injury affects nerve fibers, which can lead to a disruption in nerve communication that affects a person's physical and cognitive abilities.