The concussion phenomenon
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Transcript of The concussion phenomenon
Introduction
• By The Numbers
• Concussion Defined
• Signs And Symptoms
• Newton Applied
• Your Obligations
• Resources
Disclaimers
• Founder - The Institute of Sport Science & Athletic Conditioning
• Director - Dominate Your Game!• State of NV Director - NSCA• State of NV Chair - NAS• Judge - INBA• Graduate student, Exercise Science - Concordia
University• Sport Science Consultant - Xyience Nutrition
What is a Concussion?
• *Not a medical course*
• No universally accepted all-encompassing definition
• "…a complex pathophysiological process affecting the brain, induced by traumatic biomechanical forces." (Cantu RC 2006)
• Traumatic Brain Injury (TBI)
Of the estimated 1,500,000 people who
sustain TBIs each year in the United States:
• 1.1 million treated & released from an Emergency Dept.
• 235,000 hospitalized
• 50,000 die
• 80,000 experience onset of long-term effects from a TBI
• 5.3 million Americans (2% of population) living with a disability as a result of a TBI
What happens to your brain
• Initiated by a mechanical occurrence
• Causing a mechanical incident
• Resulting in a chemical / biological episode
STAGE 1:
The brain slams against the skull:
• Blood vessels tear, causing bleeding
• The axons that carry impulses from neuron to neuron stretch unnaturally, garbling their signals
• The neurons fire simultaneously, causing a miniseizure.
*Neuropsychologist David Hovda, UCLA’s Brain Injury Research Center
STAGE 2:
• As they fire, K+ rushes out of them and Ca+ rushes in, clogging the neurons’ mitochondria.
• To fuel the absorption of new potassium, the neuron consumes glucose.
• Metabolizing glucose creates lactate, an acid that damages cell walls.
STAGE 3:
• The calcium-clogged mitochondria do not get needed O2.
• This causes a neuronal energy crisis. Blood flow drops and cells begin to die.
• Contusion and Edema • Skull Fracture• Intracranial Hematoma
– Subdural or epidural– A blood vessel ruptures – Collection of blood compresses
brain tissue.
• Left: Arrows indicate an epidural hematoma, a collection of blood between the skull and the outer covering of the brain, which is compressing the right frontal lobe. • Right: Arrows highlights tumors in both sides of the brain.
Related Conditions
*Mayo Clinic staff 1998-2005 Mayo Foundation for Medical Education and Research.
Symptoms
• Unequal pupil size
• Vacant Stare
• Tinnitus (ringing in the ears)
• Nausea & Vomiting
• Delayed verbal responses
• Delayed motor responses
• Confusion & inability to focus
• Memory deficits
*www.headinjury.com/sports.htm, www.mayoclinic.com
• Emotions out of proportion
• Slurred or incoherent speech
• Gross observable incoordination
• Disorientation (time, date, location)
• Any period of LOC
• Headaches and Irritability
• Sleep Disturbances
• Depression may develop
Long Term?
• ALS
– Chronic traumatic encephalopathy
• Alzheimer's
• Various Symptoms of Dementia
Guskiewicz KM, et al, 2005
Comparison of concussion grading scales
Grade I Grade II Grade III
Cantu guidelines
Post-traumatic amnesia <30 minutes, no loss of
consciousness
Loss of consciousness <5 minutes or
amnesia lasting 30 minutes–24 hours
Loss of consciousness >5 minutes or amnesia
>24 hours
Colorado Medical Society
guidelines
Confusion, no loss of consciousness
Confusion, post-traumatic amnesia, no loss of consciousness
Any loss of consciousness
American Academy of Neurology guidelines
Confusion, symptoms last <15 minutes, no loss of consciousness
Symptoms last >15 minutes, no loss
of consciousness
Loss of consciousness (IIIa, coma lasts seconds, IIIb for
minutes)
Types
• Impact– Head hitting an object– Object hitting head
• Non-Impact– Whiplash– Sudden change in direction
The Physics
• Newton’s Three Laws of Motion
• Conservation of Momentum & Energy
• Centripetal Force
First Law
• An object at rest or in motion will stay at rest or in motion in the same direction and speed unless an outside force acts upon it.
• Inertia
• Driving in a car
• Standing on Earth?
Conservation of Momentum & Energy
Second Law
• The acceleration of an object depends directly upon the net force acting upon the object, and
inversely upon the mass of the object. • F=ma
Third Law
• For every action, there is an equal and opposite reaction.
Centripetal Force
• “Center Seeking”
• F=mv2/r
• Force pulls object inward
• However, object wants to continue in a straight line (Newton’s First Law)
• Therefore, object feels force of being pushed out – Centrifugal Force (Newton’s Third Law)
Head Injury Criterion (HIC)
• HIC is a measure of the likelihood of head injury arising from an impact, defined as:
Large accelerations may be tolerated over very short periods of time.
HIC continued…
• At a HIC of 1000, one in six people will suffer a life-threatening injury to their brain
• In one study, concussions were found to occur at HIC=250 in most athletes. (Viano D C, 2006)
Newton Applied
• Though average adult head is approximately 5 kg
• Not isolated object (depending on direction of force)
• Total body weight and velocity
• Conservation once again
Which exerts more Gs?
Jet Barrel Roll Football Collision
• Average?
• About 9 Gs
• Average: 6’ tall, 200 lbs.
• Average Speed: 40 yard in 4.8 seconds
• 150 Gs!!
By way of comparison…
Damon vs. Jackson(2003 AL Playoffs)
Newton Applied Again
• Jackson: 12 mph• Damon: 14 mph• = Closing Velocity: 26 mph• = 90 Gs• = Baseball traveling 180 mph• PLUS: Rotational velocity• PLUS: Impact with ground• Multiple sights of bleeding/damage
*Courtesy of FSN, 2007
• Collegiate Stats (per 1,000 athletes)
– Football: 3.52 per game/practice
– Ice Hockey: 2 per game/practice
– Men’s Soccer: 1.13 per game/practice
– Women’s Soccer: 1.8 per game/practice
– A study of collegiate football players showed that players with >3 concussions had 3x the rate of depression.
Prevalence of Concussions in Sports
*Courtesy of the NCAA
What Can You Do?
• Recognize conditions prone to TBIs
• Be aware of your athletes’ movements
• Analyze your athletes’ patterns
• Special attention to children
– Marshmallow on top of piece of spaghetti
What Can You Do?
• Be observant of your clients’ environments
• Insist that your clients use all protective gear needed
• Do not allow a return to training without physician’s specific release
• Understand TBIs can occur through different mechanisms
More importantly…
• Know your athletes before the season begins. This provides the staff (coaches, ATCs, etc.) an opportunity to:
• Assess concussion risk factors
• Provide education to athletes on the signs and symptoms of concussions
• Administer baseline concussion testing
• Establish an emergency procedure protocol to follow in the event of a concussion
A Recent Article…
• Helmets will never prevent concussions
• ~ Seatbelts will never prevent automobile fatalities
• So, just stop?
• Maybe not a rule or player issues…
So, what does this all mean?
• Sport Science has improved athletes exponentially over the last decade
• As strength coaches, we are doing our jobs
• However, have game rules & the equipment kept up with this progress?
• Our responsibility to keep our athletes safe
As an Interesting Side Note…• Study looked at the neuroprotective effects of Creatine (Cr)• 39 children and adolescents, aged between 1 and 18 years of age,
with TBI• Cr was administered for 6 months, at a dose of 0.4 g/kg in an oral
suspension form daily. • By comparison, that is equal to 45.5 grams daily for a 250 pound
individual• Improved results in several parameters, including duration of post
traumatic amnesia (PTA), duration of intubation, and intensive care unit stay.
• Significant improvement was also recorded in the categories of headache, dizziness, and fatigue aspects in all patients
• All with no negative side effects
*Sakellaris G, Nasis G, et al. Prevention of traumatic headache, dizziness and fatigue with creatine administration. A pilot study. Acta Paediatr. Jan 2008;97(1):31-34.
Believe it or not…
*Courtesy of National Geographic Channel
Resources
• http://www.cdc.gov/concussion/sports/resources.html• http://www.springerlink.com/content/r859713q00204262• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC155415/• http://www.ncbi.nlm.nih.gov/pubmed/16239884
Questions?