The Concussion Blog

I have been asked to write about concussions from time to time.  I attempted a chapter on concussions for a book at some point, over the next few weeks I will post this chapter, as I wrote it, no matter how horrible it is.  After all I am not an author, but at least you can take a look.  This particular chapter deals with concussions in the sport of football.  We all should know this injury can be sustained in any sport.  Because football is the biggest draw of sporting eyes I felt it was best to present it in this way. (Part I)

What is a Concussion

Simply put; a concussion is a disruption of normal brain function.  More specifically a concussion is a traumatic brain injury, which has developed due to unnatural forces applied to the brain, resulting in symptoms indicative with the injury.

Webster Dictionary[i] defines concussion as (noun);

1. 1.      A shaking or agitation; a shock; caused by the collision of two bodies.
2. 2.      (Med.) A condition of lowered functional activity, without visible structural change, produced in an organ by a shock, as by fall or blow; as, a concussion of the brain.

 

In terms of football and sports, concussions can be further defined as it has been at About.com[ii];

“Concussions are traumatic head injuries that occur from both mild and severe blows to the head. Some head injuries may appear to be mild but research is finding that concussions can have serious, long-term effects, especially repeat head injuries or cumulative concussions.

A concussion is typically caused by a severe head trauma during which the brain moves violently within the skull. The brain cells all fire at once, much like a seizure. Some studies show that patients who suffer a concussion appear to have the brain activity of people in a coma.

A concussion may result from a fall in which the head strikes against an object or a moving object strikes the head. A suddenly induced turning movement such as a blow that twists the head (like a punch to the side of the face) is more likely to produce unconsciousness. However, significant jarring in any direction can produce unconsciousness.

In 2004, data has collected from the head impact telemetry system used in the NFL concussion studies found that 58 of 623 (9.3 percent) of professional football players who suffered a concussion also had a loss of consciousness.”

The take home message from both of the sources is that the brain is “rattled” in some fashion that will produce a symptomatic response that the individual will feel (symptoms) and even exhibit (signs).  In the sport of football this can occur on EVERY play.

At the snap of the ball the offensive and defensive players engage in a “war” to gain an advantage, regularly delivering and absorbing blows that would satisfy the above criteria.  The linemen often hit helmet-to-helmet, while the perimeter players (quarterbacks, running backs, receivers, linebackers, and defensive backs) tackle or are tackled in a violent collision that elicit forces far greater than what is “normal” for people like us reading this book.  It is the nature of the game.

The signs (exhibiting or objective data) and symptoms (feeling or subjective data) of a concussion vary in each and every case, they can even manifest differently across genders[iii].  Below are the signs (outwardly seen and measurable) of a concussion;

• Grabbing Head
• Vomiting
• “Unsteady” on Feet
• Unequal Pupils
• Unconsciousness
• Irritability
• Personality Changes
• Memory Loss
• Amnesia

Below are the symptoms (reported) of a concussion;

• Headache
• Dizziness
• Nausea
• Tinnitus (ringing in ears)
• Vision Disturbance
• Fatigue
• Depression
• Memory Loss
• Feeling “Foggy”
• Poor Concentration
• Sleep Disturbances

It is important to remember that this is not an ALL-INCLUSIVE list.  Any disorders with normal activity associated with the brain should be considered symptoms.  Even though headache is one of the top reported conditions associated with concussion, the brain could still be injured even if there is not a headache present.  Likewise, if a headache resolves this does not mean the injury has resolved; other factors, signs and symptoms could still be present alluding to the fact that the brain is still experiencing concussive effects.

A good example is a case that I had a few years back with a high school athlete.  His normal demeanor was that of a “class clown”, funny, outgoing, and over the top.  After a head injury he became reserved, serious, withheld from activity and people; all the while not exhibiting the “normal” signs and symptoms.  This was obvious to me that he was having serious changes in the overall health, only observed by me and his family.

Also with school aged kids; a slip in grades is a huge indicator and one that not only parents and athletic trainers should be aware of, but school teachers, coaches and administrators should be aware of.

There is much more happening at the smallest of levels in the body, the physiological response if you will.  We could go deep into the actual happenings even at the cellular level, but most of those words and concepts may miss you, the audience.  It is important however to give an explanation as to what is occurring in the brain during this injury.  The best and most comprehensible description was given by John Doherty after interviewing David Hovda, PhD of the University of California – Los Angeles[iv];

When there is a sufficient blow to the brain, the membranes of the affected nerve cells in the brain are stretched or twisted, allowing potassium to exit those cells, which triggers those cells to depolarize, thus the phenomenon of seeing stars if the affected area is involved with sight or ringing in the ears if the affected area is involved with hearing. The exit of potassium (K+) peaks approximately two minutes after the incident but continues for another 3-4 minutes.

Then, until the chemical balance is somewhat restored, those neurons (nerve cells) are unable to fire again. Furthermore, in a protective reflex of sorts, surrounding cells begin to shut down, a process Hovda calls “spreading depression.”

If enough cells become depressed, confusion, amnesia, and even loss of consciousness result.

Meanwhile, in an attempt to recover, the brain starts using up massive amounts of blood sugar and will continue to do so for as long as 30 minutes. This overuse of this glucose results in the production of lactic acid which, in excess amounts, inhibits brain function.

During the period of the brain being compromised from the hit, calcium – an energy sapping electrolyte – is allowed into the neuron due to the potassium leaving and although it takes a matter of seconds to get in, calcium can take up to four days to exit the neuron[v].  During the immediate aftermath the brain calls on more blood to make up for the lost glucose, however after the initial response, the brain and body decrease blood flow to the brain for reasons unknown[vi].  This lack of blood flow contributes to the delay in return to normal chemical makeup.

The significance of the “non-normal” condition the brain is experiencing post-concussion is the lack of protection at a cellular level, thus predisposing the brain to further and greater injury.  Until the “spreading depression” of the cells in the brain has normalized, a very small insult to the brain can elicit the concussive response or worse.  One must remember that the brain can receive an insult (negative problem) by simply being used for something as minor as reading or concentrating.  However, a blow to the body or head can be a much more dangerous insult resulting in devastating effects that are often irreversible.

There are some myths with this injury that many believe; we will address these throughout the chapter.  These are the top myths that you may or may not know;

• If you weren’t knocked out you don’t have a concussion
• You should play though the pain – get back in the game
• Concussion is a minor injury with no long-term effects
• Everyone gets better in a week
• If there is no visible injury, everything is OK
• Once the headache is gone everything will be fine
• Helmets protect and prevent concussions

Second Impact Syndrome

The brain develops on average into the early to mid-20’s[vii] and during this time of development any insults to the brain can produce more complicated symptoms and effects.  One such situation that pertains to concussions/head trauma is Second Impact Syndrome (SIS); an acute, usually fatal, brain swelling and increased cranial pressure, caused by repeated head trauma in a short space of time, so that a second concussion occurs before recovery from a previous concussion is complete[viii].

Second Impact Syndrome has been noted in various different articles and papers to only occur in adolescents, those that still have a developing brain, SIS is often fatal and almost always results in permanent disability[ix].  While the brain is recovering from the first injury of concussion and receives a second insult the brain responds with uncontrollable bleeding causing pressure to build in the skull and effectively shutting down the brain due to the intracranial pressure[x].

In the sport of college football there has not been a noted case of SIS, however it should be known that the players are generally between the ages of 17-24, the later end of brain development.  This condition is seen more with high school aged players, as of 13 years ago only 17 cases were identified[xi], however the risk remains for anyone that has a still developing brain.

Second Impact Syndrome is one of the scariest presentations of injury that we can see as an athletic trainer or medical professional.  A person that experiences this condition will present with extreme headache, usually standing and conversing, and then deteriorate rapidly from there.  The individual experiencing SIS will then most likely lose consciousness and begin to seize.  As pressure in the brain builds up the areas of the brain responsible for breathing and general life are getting crushed and beginning to shut down.  Rapid entrance into advanced life support is needed along with transport to a facility that can perform an immediate emergency surgery of the brain/skull, pressure must be released in order to survive.  Surgeons can accomplish this by drilling into the skull and even removing portions of the skull to allow for the brain to swell.  There is nothing more than prevention that can keep SIS from occurring, meaning that treatment of the original concussion is paramount.