Don Cherry, Concussions & Traumatic Brain Injury (TBI) in Hockey, War & Cars

AN OPEN  LETTER TO DON CHERRY

Hi Don,

I’m your neighbour, just a few blocks down from your place. I watched you on CBC  ‘Hockey Night in Canada’ the other evening talking about former NHL hockey enforcers complaining about concussions and brain trauma. Imagine that!

Don, I like watching you but you seem a bit misguided. I really want to help you. So in order that you be able to make more informed choices before speaking, I am enclosing a bit of information on brain trauma injury and concussions.

I love hockey but then I only watch it, haven’t played it since I was a kid nor do my kids play it. It’s safer that way but this information applies to those who do play hockey, football, rugby or any other contact sport. Oh, it also applies to war combat participants and particularly to auto accident victims and the many, many other people with brain trauma injuries.  Read on, Don. Some of this is tough stuff so if you have any questions, give me a holler or drop by for a coffee.

Traumatic Brain Injury

Gargollo and Adams state that one of the leading causes of death and disability in the industrialized world is due to head trauma and TBI. Over 50,000 people die every year in the U.S. due to TBI.

The incidence for traumatic brain injury is about 100 hospitalized cases per 100,000 population. (Kraus & McArthur, 1999) as compared to 4 per 100,000 with spinal cord injury and 10 per 100,000 for cerebral palsy. Thus, it has been estimated that a head injury occurs every seven seconds, and hospital emergency rooms annually treat 1 million patients for brain injuries.

While the incidence of stroke approaches that of TBI, it usually occurs in an older population. TBI is an injury that effects a younger population. The occurrence peaks with age groups below 5 years, between 15-24 years, and over 70 years. The maximum peaks are 133 per 100,000 in the 15-24 year age range and 165 per 100,000 in the over 65 age group.

In the United States, as a result of good roadside care and improvements in intensive care, secondary injury is rarer today than 15 years ago. The mortality (death) rate for TBI is 30 per 100,000. Of those who die, 50% do so within the first 2 hours of their injury. Severe blunt trauma has a mortality rate of 30% if TBI is involved, whereas without TBI the death rate for blunt trauma is 1%. Trauma is still the leading cause of death from people ages 1 to 44.

An estimated 50,000 individuals per year die of traumatic brain injury in the U.S. and an estimated 70,000 people experience long-term impairment and complications due to TBI. Ninety-three percent of persons diagnosed with a moderate head injury and 42% of those with severe head injury survive their injury and are discharged from acute care. There are approximately 5.3 million Americans, or more than 2 percent of the U.S. population, that live with disabilities associated with such injuries.

The incidence of hospitalization for traumatic brain injury in the US appears to be diminishing over time (200 per 100,000 hospitalized cases of head injury in early-1980’s based on population estimates; about 100 per 100,000 in 1995) since milder head injuries are no longer being hospitalized. The number of more severe head injuries has actually risen slightly, possibly due to increased post-2 hour survival.

In 2007, a VA mandatory screening program looked at 61,285 veterans of the wars and identified that 19.2 percent on the screening questionnaire as potentially suffering from traumatic brain injuries. The Defense and Veterans Brain Injury Center, a joint Pentagon-VA research effort, 14 percent to 20 percent of troops in previous conflicts have had traumatic brain injuries. The Center states that there are reasons to expect a higher percentage among troops in the current conflicts because improved body armour has made soldiers more likely to survive injuries that would have been fatal in previous wars as well as because of the prevalence of roadside bombs and rocket-propelled grenades attacks on U.S. forces. The blasts from such weapons can easily cause concussive brain injuries.

The US Military has also experienced significant TBI cases amongst its soldiers stationed in Afghanistan and Iraq (http://ptsdcombat.blogspot.com/2007/11/va-about-6-percent-of-oefoif-vets.html). The US military hospital in Landstuhl also began screening every patient coming in from Iraq and Afghanistan for TBI in May 2006 after doctors noticed that many of them had inexplicable problems that later were diagnosed as TBI. Since then, 23 percent of the 10,000 patients screened for TBI have tested positive. About 98 percent of those have “mild” TBI, which by definition cannot be detected with most brain scanning technology.

Jones et al (King’s Centre for Military Health Research) have written a review looking at the nature of shell shock, its clinical presentation, the military context, hypotheses of causation and issues of management and consider whether there are contemporary relevancies to the current signature injury of the Iraq and Afghanistan conflicts, known as Mild Traumatic Brain Injury (MTBI). A similar Canadian perspective supporting the above is provided in an article by Thompson et al (2008).

Professor Jones explains: “Mild traumatic brain injury is not a new disorder confined to Iraq and Afghanistan. Its symptoms and military context bear strong similarities with shell shock in World War One and post-concussional syndrome in World War Two. There are dangers not only in assuming that MTBI is novel but in characterizing it solely as an organic injury. The evidence of the last two World Wars is that brain injury often arises in a context of psychological distress, requiring us to consider the physical but also the mental health of those with concussive injuries.”

Research into the “civilian” form of mTBI – generally caused by concussions – shows that most people will fully recover over time with rest and by avoiding additional concussions. But experts aren’t sure that injuries caused by blasts heal the same way. While much is known about the way the brain reacts to concussions caused by car accidents or sports injuries, researchers are only beginning to examine its response to explosions. Recent studies suggest that blasts might slowly kill brain cells over months and years, leading to permanent loss of function. Those whose symptoms don’t go away, and the people close to them, have to learn to live with the condition.

Causes of TBI

Most individuals are injured in motor vehicle crashes. The national statistics cite between 50 and 70% of traumatic brain injuries are the result of a motor vehicle crash (MVC). The ICRC data found that MVC’s are the cause of 64% of TBI’s and in over half of these, 53%, the driver was under the influence of alcohol.

Other causes were gunshot wounds to the brain (13%) and assaults (8%). Severe head injury resulting from playing sports is rare, less than 1% of all cases. ICRC data shows 15% of injuries during the 5-year period of data collection were intentional. The cause can be assault with a blunt instrument or a gun, with 4% of the intentional injuries being suicide attempts.

Cost of TBI

Cost breakdown can be differentiated into either financial costs or the cost of life. With every death that results from a TBI, on the average, there are 38 years of living lost. The care for people with new-onset TBI cost an estimated $6.5 billion in 1993 dollars. Ongoing care for people with an existing head injury costs $13.5 billion in 1993 dollars. For a person in a persistent nonresponsive state, which used to be called a vegetative state, the lifetime costs are over 3 million dollars. Note that, in most cases, these individuals do not live for a full life span.

The life expectancy of most head-injured persons is similar to that of the average individual. For a severe head injury the lifetime costs are over $3 million; for moderate injury, $941,000; and for mild trauma $85,000.

CAUTION: DON, SORRY BUT THIS IS THE MORE TECHNICAL PART… TALK TO YOUR DOCTOR:)

Type of Brain Injuries

Acquired Brain Injury and Traumatic Brain Injury (TBI)

An acquired brain injury is damage to the brain caused by anything that was acquired – such as a stroke, or a traumatic injury, as compared to a condition that was inherited. Traumatic brain injury (TBI) is more specific as it implies trauma to the brain caused by an external force impinging upon the head and brain. It does not define the force or the severity of the force,

1)    Traumatic Brain Injury (TBI)

When dealing with traumatic brain injury, there are often other injuries as well. The TBI Model Systems National Database shows that 72% of the TBI admissions had fractures. There were cranial nerve deficits in 17% of cases and 4% of the individuals had a spinal cord injury. Often it is necessary to deal with other injuries in addition to the head injury.

i)         Localized Injury

Brain tissue is soft and essentially is floating, supported in fluid within the skull. Brain tissue can therefore be compressed, pulled, and stretched. With a localized injury there can be contusions (bruising) to the brain in a particular area.

When there is acceleration and deceleration, such as occurs in a traumatic injury, the brain can strike the inside of the skull. It can bounce back and forth, hitting the back of the skull and the front of the skull, causing bruising to the brain. Contusions can occur anywhere, but the frontal and temporal areas are more susceptible to injury.

Another type of localized injury is a hematoma i.e. a blood clot Again the movement of the brain within the skull causes the blood vessels that traverse the surface of the brain to be pulled, stretched, or torn. There are several forms of hematoma:

a)      subdural hematoma: blood clot below one of the protective layers that surround and envelop the brain. This is a venous bleed.

b)       epidural hematoma: blood clot between one protective layer of the brain (the dura) and the skull. This is usually an arterial bleed.

c)   intracerebral hematoma or hemorrhage: bleeding within the brain tissue itself.

One of the major problems caused by hematomas is that they press the soft tissue compressing the brain out of the way and eventually, if the pressure is sufficient and treatment (usually surgery) is not forthcoming, the person dies.

ii)        Diffuse Axonal Injury

Axons extend from each neuron cell body in the brain and allow communication from one neuron to another neuron. During acceleration/deceleration, axons also pull, stretch, tear, etc., and where there is sufficient injury to the axon, the neuron can either immediately die or within a few days. Thia type of injury can be extensive and not confined to one area of the brain. This kind of injury also does not show up on a CT scan and most importantly, cannot be reversed.

iii)       Secondary Brain Injury                                                                                                                                  

Secondary brain injury includes insufficient oxygen (hypoxia) to the brain (such as when a person is not breathing or their blood pressure is too low) or increased intracranial pressure i.e. significant swelling (edema). Hematomas and edema can prevent blood from getting into the brain tissue. Prevention of secondary injury to the brain is the treatment goal i.e. maintaining sufficient cerebral perfusion pressure of blood to provide sufficient oxygen to brain tissue.

Current TBI treatment does not include the use of neuroprotectants to prevent neuronal cell death. However, there is a large body of evidence to support the hypothesis that brain injury can cause activation of caspase enzymes, proteolytic enzymes that degrade essential protein machinery that is the hallmark of apoptosis. This results in the death of neurons in this clinical context and biological agents that would act as anti-apoptotic inhibitors would prove to be both life-saving and critical to the effective reduction of any acute secondary complications as well as reduction of any permanent disabilities.

References for information contained in this blog article are available upon request. Please contact me if you would like any additional information regarding this exciting field of research.

About the author

Myron Pyzyk is the Principal Consultant and CEO of Marenon Consulting. He has over 20 years of experience in the pharmaceutical, nutraceutical & biotech industries. Mr. Pyzyk holds a B.Sc in psychology from the University of Alberta (Edmonton, Canada) and a graduate degree (M.S.) in clinical nutrition from the University of Bridgeport, Connecticut.