1. No category

Concussion: What is it and What
Do We Do About it?
Farah Hameed, MD
Department of Rehabilitation and Regenerative Medicine
May 10, 2014
Assistant Professor
Columbia University Medical Center/New York Presbyterian Hospital
Disclosure Statement of Financial Interest
I, Farah Hameed, DO NOT have a financial
interest/arrangement or affiliation with one or
more organizations that could be perceived as a
real or apparent conflict of interest in the
context of the subject of this presentation.
Roadmap
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Definition
Epidemiology/Prevalence
Risk Factors
Signs/Symptoms
Management
Prognostication
Outcomes
Prevention?
Concussion in the News
Definition of a Concussion
• Zurich conference 2013:
– “Concussion is a brain injury and is defined as a complex pathophysiological process
affecting the brain, induced by biomechanical forces.”
• May be caused by direct/indirect forces up to 36h
after trauma
• Rapid onset of short lived impairment of neurologic
function
• Concussion is largely a functional disturbance
instead of a structural injury
• Results in a graded set of clinical symptoms;
uncommon to involve loss of consciousness (LOC)
McCrory P, Meeuwisse WH, Aubry M, Cantu RC, Dvořák J, Echemendia RJ, Engebretsen L, Johnston KM, Kutcher JS, Raftery M, Sills A, Benson BW, Davis GA, Ellenbogen R, Guskiewicz KM, Herring
SA, Iverson GL, Jordan BD, Kissick J, McCrea M, McIntosh AS, Maddocks DL, Makdissi M, Purcell L, Putukian M, Schneider K, Tator CH, Turner M. Consensus statement on concussion in sport--the
4th International Conference on Concussion in Sport held in Zurich, November 2012. PM R. 2013 Apr;5(4):255-79.
Epidemiology
• In 1998, CDC estimated
that approximately
300,000 concussive
injuries happen per
year
• CDC estimate now:
1.6-3.8 million sports
related concussions
each year
• Diagnosis rates on
the rise
Rosenthal JA, Foraker RE, Collins CL, Comstock RD. National High School Athlete Concussion Rates From 2005-2006 to 2011-2012. Am J Sports Med. 2014 Apr 16.
Concussion Legislation
• In 2009, Washington state passed
Zachary Lystedt law
• Concussion Management and
Awareness Act 2012 passed for NY
state public schools
– Mandates education for coaches,
athletic trainers etc.
– Information provided to parents
– Prompt removal from athletics
until medical clearance
– Academic accommodations if
needed
http://www.cdc.gov/concussion/policies.html
Concussion Rates for HS Athletes 2008-2010
Marar M, McIlvain NM, Fields SK, Comstock RD. Epidemiology of concussions among United States high school athletes in 20 sports. Am J Sports Med. 2012 Apr;40(4):747-55.
Concussion Rates in HS Athletes 2008-2010
Marar M, McIlvain NM, Fields SK, Comstock RD. Epidemiology of concussions among United States high school athletes in 20 sports. Am J Sports Med. 2012 Apr;40(4):747-55.
Younger Athletes
• Younger athletes have a longer
window for subsequent
concussions
• Young athletes brains are still
DEVELOPING
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Brain water content
Cerebral blood volume
Level of myelination
Skull geometry
Suture elasticity
Less developed neck/shoulder
musculature
Guskiewicz KM, Valovich McLeod TC. Pediatric sports-related concussion. PM R. 2011 Apr;3(4):353-64
Physiology of Concussion
• Abrupt neuronal
depolarization
• Release of excitatory
neurotransmitters
• Ionic shifts
• Altered glucose
metabolism (increased)
• Altered cerebral blood
flow (decreased)
• Impaired axonal function
Giza CC, Hovda DA. The Neurometabolic Cascade of Concussion. J Athl Train. 2001 Sep;36(3):228-235.
Signs of a Concussion
PHYSICAL
Vision changes
Balance problems
Sleep Disturbance
COGNITIVE
“In a fog”
Slowed down
Difficulty
concentrating
SOMATIC
Headache
Nausea
Dizziness
EMOTIONAL
Irritable
Anxious
Sadness
Signs/Symptoms
Early (minutes to hours later)
• Headache
• Dizziness or vertigo
• Lack of awareness of
surroundings
• Nausea or vomiting
• Balance problems
• Visual disturbance
• Mental confusion
• Amnesia (retro-/anterograde)
• Perseveration
Master CL, Balcer L, Collins M. Concussion. Ann Intern Med. 2014 Feb 4;160(3):ITC2-1.
Late (days to weeks later)
• Persistent low-grade
headache
• Lightheadedness
• Poor attention, concentration
• Memory dysfunction
• Easy fatigability
• Irritability, frustration
• Intolerance of loud noises
• Anxiety or depressed mood
• Numbness or tingling
• Sleep disturbance
Risk Factors
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Concussion history
– 2.8x with 2 prior
– 3.5x with 3 prior
– 6x with LOC
High contact sports
Age
Gender (2-2.5x with females)
Neck strength
Force/Location of impact
Frequency/timing/fatigue
Anticipation of collision
+/- Protective gear
•
Can be complicated by history of:
– Migraines
– Anxiety
– Depression
– ADHD
– Learning disabilities
– Cognitive delays
• Family History
– ApoE gene
• G219T TT subtype; 3x
higher
– Tau protein, chromosome 17
NO KNOWN THRESHOLD FOR CONCUSSIVE INJURY!
Kutcher JS, Eckner JT. At-risk populations in sports-related concussion. Curr Sports Med Rep. 2010 Jan-Feb;9(1):16-20.
Acute Assessment Tools
• SCAT 3/Child SCAT 3
– Glasgow Coma Scale
– Maddocks Score
– Symptom Score
– Cognitive Assessment
– Neck Examination
– Balance examination
– Coordination examination
– Recall
Chiild scat 3 - bjsm.bmj.com/content/47/5/263.full.pdf
ACE - www.cdc.gov/concussion/headsup/pdf/ace-a.pdf ‎
• Acute Concussion Eval (ACE)
– Injury description
– Symptom checklist
– Risk factors
– Red flags
– Follow up plan
LOC/Glasgow Coma Scale
Maddocks Score
Symptoms
Symptoms
Balance Error Scoring System (BESS)
- Non-dominant foot behind
- 20 second each
- Total 6 trials
- Child BESS
- 2 trials (double, tandem – no foam)
- Tandem gait
Bell DR, Guskiewicz KM, Clark MA, Padua DA. Systematic review of the balance error scoring system. Sports Health. 2011 May;3(3):287-95.
Cognitive Assessment
Orientation
Immediate Memory
Concentration
Recall
Clinical Examination
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Physical neurologic
examination:
– CN (*oculomotor system)
– Strength
– Reflexes
– Sensation
– Cerebellar testing
(coordination)
Balance testing
– BESS testing
Symptom scores
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Cognitive Assessment:
– Mini mental
– Orientation
– Serial 7’s, months
backwards
– Series of digits backwards
– Immediate/recall memory
Musculoskeletal exam
– Cervical spine tenderness,
ROM, posture, muscular
imbalance
Vestibular Oculomotor Test
 Neurocognitive testing
Armstrong C. Evaluation and Management of Concussion in Athletes: Recommendations from the AAN. Am Fam Physician. 2014 Apr 1;89(7):585-7.
Vestibular Oculomotor Screening – UPMC
•
Smooth pursuits: Examiner’s finger moves
horizontally, progressively increasing speed
•
Saccades: Examiner’s fingers held at shoulderwidth and forehead and chin distance to test
horizontally & vertically
•
Gaze stability: Patient fixes gaze on examiner’s
thumb while nodding (vertical) and then shaking
(horizontal) head
•
Convergence insufficiency and Accomodation:
Patient takes a pen with letters and holds at arm’s
length and brings towards their nose
Heitger MH, Jones RD, Macleod AD, Snell DL, Frampton CM, Anderson TJ. Impaired eye movements in post-concussion syndrome indicate suboptimal brain function beyond the influence of
depression, malingering or intellectual ability. Brain. 2009 Oct;132(Pt 10):2850-70.
medicine.utah.edu/pmr/.../2013/Michael%20Collins%202013.
King-Devick (K-D) Test
• Based on the detection of
impaired eye movements and
saccades
• 3 separate trials
– “Read numbers as fast as you can
without mistakes”
• High test-retest reliability
• Accurate method to rapidly
identify athletes with overt
head trauma
• Laypersons can utilize this
test reliably
Galetta KM, Brandes LE, Maki K, Dziemianowicz MS, Laudano E, Allen M, Lawler K, Sennett B, Wiebe D, Devick S, Messner LV, Galetta SL, Balcer LJ. The King-Devick test and sports-related
concussion: study of a rapid visual screening tool in a collegiate cohort. J Neurol Sci. 2011 Oct 15;309(1-2):34-9. doi: 10.1016/j.jns.2011.07.039.
Diagnostic Tools – Research
Biomarkers
• S-100Beta protein
• Neuron Specific Enolase (NSE)
• Cleaved Tau protein
Measures of vestibular-occular
function
• Sensory Organization Test
• Eye tracking devices
Radiographic Imaging
 Diffusion Tensor Imaging (DTI)
 Single Photon Emission
Computerized Tomography
(SPECT)
 Positron Emission Tomography
(PET)
 Functional Magnetic Resonance
Imaging (fMRI)
Davis GA, Iverson GL, Guskiewicz KM, Ptito A, Johnston KM. Contributions of neuroimaging, balance testing, electrophysiology and blood markers to the assessment of sport-related
concussion. Br J Sports Med. 2009 May;43 Suppl 1:i36-45.
Guidelines for Neuroimaging
• Criteria for hospital/ED evaluation:
– Worsening headache
– Athlete is very drowsy or cannot be awakened
– Inability to recognize people or places
– Repeated emesis
– Unusual or very irritable behavior
** Recent study by Meehan
*
et al evaluating rates of
– Seizures
concussion 2002-6
– Weakness
demonstrated that 69% of
– Unsteady gait
pediatric patients dx with
concussion had radiographic
imaging
Scorza KA, Raleigh MF, O'Connor FG. Current concepts in concussion: evaluation and management. Am Fam Physician. 2012 Jan 15;85(2):123-32.
Meehan WP 3rd, Mannix R. Pediatric concussions in United States emergency departments in the years 2002 to 2006. J Pediatr. 2010 Dec;157(6):889-93.
Management
Cognitive Rest Avoid text messaging/video games
Limit television and computer use
Decrease schoolwork
Avoid activities that require
attention/concentration
Physical Rest
Severe or worsening
headache, persistent vomiting
or seizures may suggest need
for emergent evaluation
Avoid any physical activity that exacerbates
symptoms (aerobic exercise, weights, chores)
** Education on what to expect
** What symptoms to look for
• Documentation of current symptoms
• Follow up and track changes in symptoms
Purcell LK; Canadian Paediatric Society, Healthy Active Living and Sports Medicine Committee. Sport-related concussion: Evaluation and management. Paediatr Child Health. 2014 Mar;19(3):153-65.
Cognitive Rest
• 335 patients, within 3
weeks of injury
– Mean age 15
– Mean previous
concussions 0.76
– Mean PCSS score 30
– Mean duration of sx
43 days
• Found that increased
cognitive activity is
associated with longer
recovery
Brown NJ, Mannix RC, O'Brien MJ, Gostine D, Collins MW, Meehan WP 3rd. Effect of cognitive activity level on duration of post-concussion symptoms. Pediatrics. 2014 Feb;133(2):e299-304.
Return to School
• Alert school personnel to injury, initiate slow reintegration
– Avoid symptom exacerbation
– Forgive missed assignments, more time for tests/homework, standard
breaks and rest periods, distraction free work areas, note taker
• Relative rest—Reintroduce (5–15 minutes) of cognitive activities
• Homework/work at home—Increase to 20–30 minutes to build stamina
• Return to school—After tolerating 1–2 cumulative hours of work at
home partial-day school/work with accommodations
• Full day—With accommodations for full work load, limit make up work
• Full return to school—Full day, full work load, fully caught up with
make- up load
Master CL, Balcer L, Collins M. Concussion. Ann Intern Med. 2014 Feb 4;160(3):ITC2-1.
Management
Graded return
to play
After rest and resolution of symptoms,
athletes may progress through this protocol
after being symptom free for 24 hours.
Each phase should take 24 hours.
Symptom and medication free
If any symptoms develop,
activity should be stopped
immediately
- Non-impact aerobic exercise
- Sport-specific non impact drills
- Non contact training drills
- Full contact practice
- Return to normal game play
Purcell LK; Canadian Paediatric Society, Healthy Active Living and Sports Medicine Committee. Sport-related concussion: Evaluation and management. Paediatr Child Health. 2014 Mar;19(3):153-65.
Second Impact Syndrome
• If an athlete returns to play before full resolution of a
concussion they are at risk for second impact syndrome
• Disruption of autoregulation of the brains blood supply
underlies second impact syndrome
– Vascular engorgement
– Diffuse cerebral swelling
– Increased intracranial pressure
– Brain herniation
– Coma and/or death
McCrory P, Davis G, Makdissi M. Second impact syndrome or cerebral swelling after sporting head injury. Curr Sports Med Rep. 2012 Jan-Feb;11(1):21-3.
Medications
• Limited role in acute concussion!
• Analgesics: may be helpful (acetaminophen, ibuprofen)
– Managed best with behavioral interventions, such as rest
and modification of activities
– Avoid daily use (prevent rebound headaches)
• Melatonin: if sleep is disordered
• Amantadine: for mental slowing or fogginess
• Amitriptyline or topiramate: for chronic daily headaches
outside of the acute phase of concussion
• Methylphenidate: persistent attention issues after TBI
• Referral for anxiety and depression medication may be
warranted in the chronic post-concussion phase
Master CL, Balcer L, Collins M. Concussion. Ann Intern Med. 2014 Feb 4;160(3):ITC2-1.
Concussion Rehabilitation
• Cervical spine ROM, strengthening, manual therapies,
postural improvements with physical therapy
• Vestibular rehabilitation for ongoing symptoms of
dizziness/balance difficulties with physical therapy
• Vision therapy for persistent visual symptoms with
occupational therapy
• Cognitive rehabilitation for memory impairments, cognitive
deficits with speech therapy
• Exercise/aerobic therapy
Alsalaheen BA, Mucha A, Morris LO, Whitney SL, Furman JM, Camiolo-Reddy CE, Collins MW, Lovell MR, Sparto PJ. Vestibular rehabilitation for dizziness and balance disorders after concussion. J Neurol
Phys Ther. 2010 Jun;34(2):87-93.
Brolinson PG. Management of sport-related concussion: a review. Clin J Sport Med. 2014 Jan;24(1):89-90.
Novel Concussion
Treatments?
• Hyperbaric oxygen
treatment
• Progesterone
• Antioxidants –
glutathione
• Omega 3 fatty acids
• Conflicting
evidence
• Could be harmful
• Risks vs benefits
• Too early to tell
Schneider KJ, Iverson GL, Emery CA, McCrory P, Herring SA, Meeuwisse WH. The effects of rest and treatment following sport-related concussion: a systematic review of the literature.
Br J Sports Med. 2013 Apr;47(5):304-7.
Roth TL, Nayak D, Atanasijevic T, Koretsky AP, Latour LL, McGavern DB. Transcranial amelioration of inflammation and cell death after brain injury. Nature. 2014 Jan 9;505(7482):223-8.
Prognostication
• The younger the child, the longer the recovery
• Greater number and severity of symptoms, the longer the
recovery
• Amnesia, prolonged headache, fatigue, fogginess, cognitive
problems, and dizziness at time of injury specifically have been
shown to have worse prognosis
• With increasing history of concussions, worse prognosis for short
and long term recovery (threshold arbitrary, ? three or more)
• ? Role of genetics
McCrea M, Guskiewicz K, Randolph C, Barr WB, Hammeke TA, Marshall SW, Powell MR, Woo Ahn K, Wang Y, Kelly JP. Incidence, clinical course, and predictors of prolonged recovery time
following sport-related concussion in high school and college athletes. J Int Neuropsychol Soc. 2013 Jan;19(1):22-33.
Makdissi M, Davis G, Jordan B, Patricios J, Purcell L, Putukian M. Revisiting the modifiers: how should the evaluation and management of acute concussions differ in specific groups?
Br J Sports Med. 2013 Apr;47(5):314-20.
Longitudinal Perspective
Acute
Injury
Repetitive
Injuries
How much is too much?
How many are too many?
Subconcussive impacts?
Who is more prone to long term
effects?
RESEARCH!!!
Risk:
- Influence on recovery
- Chronic symptoms
- Cognitive Impairment
- Neuropsychiatric
disorders
- Neurodegenerative
disease
Chronic Traumatic Encephalopathy
• Boxers (dementia pugilistica,
i.e. “punch drunk”)
– Degenerative brain disease
– Build-up of the tau protein in
the form of neurofibrillary
tangles
• CTE sufferers may display sx:
–
–
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–
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Memory impairment
Emotional instability
Erratic behavior
Depression
8-10 years after repetitive
mild brain injury
• BU Center for Study of CTE 2012
• Analyzed 85 brains from
autopsy that had repetitive mild
TBI
•
80% had changes consistent with
CTE; subjects 17-98 years old
– Biased sample population
– Need to classify it in living
patients and controls who have
had repetitive trauma without
symptoms
– ? related to total amount of
trauma and how they were
treated vs genetic
predisposition
Tator CH. Chronic traumatic encephalopathy: how serious a sports problem is it? Br J Sports Med. 2014 Jan;48(2):81-3.
McKee AC, Stern RA, Nowinski CJ, Stein TD, Alvarez VE, Daneshvar DH, Lee HS, Wojtowicz SM, Hall G, Baugh CM, Riley DO, Kubilus CA, Cormier KA, Jacobs MA, Martin BR, Abraham CR,
Ikezu T, Reichard RR, Wolozin BL, Budson AE, Goldstein LE, Kowall NW, Cantu RC. The spectrum of disease in chronic traumatic encephalopathy. Brain. 2013 Jan;136(Pt 1):43-64.
Prevention
• Education and awareness are KEY for secondary prevention
– (CDC, NATA, etc)
• Rule changes (i.e. no spearing, kickoff change, hits with crown
of head)
– Changes require a shift in attitude/expectation of players,
coaches, officials, administrators and parents
– Minimize contact/heading during practices
– Appropriate technique at a young age
– Rules need to be enforced
Benson BW, McIntosh AS, Maddocks D, Herring SA, Raftery M, Dvorák J. What are the most effective risk-reduction strategies in sport concussion? Br J Sports Med. 2013 Apr;47(5):321-6.
NFL Kickoff Rule Changes – 2011
Data courtesy of Kevin Guskiewicz, PhD, ATC
Examples in Youth Athletes
• Hockey
– No body checking in hockey until at least age 14
– No “checking from behind”
• Lacrosse
– No body checking until at least age 14
• Football
– No “spearing” with tackling
– No tackling until age 14
• Soccer
– Limiting elbow to head contact in soccer
– Heading the ball – not for kids under 10 (AYOS), ? up to 14
• Baseball
– No headfirst slides
– Chin straps for helmets
• No boxing for children/adolescents
Krauss MD. Equipment innovations and rules changes in sports. Curr Sports Med Rep. 2004 Oct;3(5):272-6.
Cervical Strengthening/Anticipation
• Low neck strength is a
potentially modifiable risk
factor for concussion
• 46 athletes total
– Males/females
– Adults/pediatrics
– Different sports
• Found that in male/females
athletes across ages, greater
isometric neck strength and
anticipatory activation
reduced kinematic loads
Eckner JT, Oh YK, Joshi MS, Richardson JK, Ashton-Miller JA. Effect of neck muscle strength and anticipatory cervical muscle activation on the kinematic response of the head to impulsive loads.
Am J Sports Med. 2014 Mar;42(3):566-76.
Concussion Proof Helmet???
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Helmets have been shown to: reduce
the risk of catastrophic injuries
– Skull fractures
– Focal injuries
Can help manage the energy in the
cranial cavity
– Riddell Revolution helmet showed
modest reduction
None have been shown to prevent
concussion
– Mouthguards
– Headbands
– May make athletes feel secure
Rowson S, Duma SM, Greenwald RM, Beckwith JG, Chu JJ, Guskiewicz KM, Mihalik JP, Crisco JJ, Wilcox BJ, McAllister TW, Maerlender AC, Broglio SP, Schnebel B, Anderson S, Brolinson PG. Can
helmet design reduce the risk of concussion in football? J Neurosurg. 2014 Apr;120(4):919-22.
Exposure:
Helmet
design
Cervical
strength
Anticipation
The Concussion Solution?
Acute
Diagnosis:
Imaging
Biomarkers
VOR testing
Symptoms
Neurocognitive
function
Impact
Biomechanics
Concussion
Balance/VOM
Prevention:
Rule Changes
Behavior
Modification
Player
Positions
Chronic effects
Acute
Treatment:
Rest
Other novel
treatments?
Thanks for Your Attention!!!
References
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McCrory P, Davis G, Makdissi M. Second impact syndrome or cerebral swelling after sporting head injury. Curr Sports Med Rep. 2012 Jan-Feb;11(1):21-3. PubMed PMID:
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Scorza KA, Raleigh MF, O'Connor FG. Current concepts in concussion: evaluation and management. Am Fam Physician. 2012 Jan 15;85(2):123-32. Review. PubMed PMID:
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Kutcher JS, Eckner JT. At-risk populations in sports-related concussion. Curr Sports Med Rep. 2010 Jan-Feb;9(1):16-20.
Davis GA, Iverson GL, Guskiewicz KM, Ptito A, Johnston KM. Contributions of neuroimaging, balance testing, electrophysiology and blood markers to the assessment of sportrelated concussion. Br J Sports Med. 2009 May;43 Suppl 1:i36-45.
Alsalaheen BA, Mucha A, Morris LO, Whitney SL, Furman JM, Camiolo-Reddy CE, Collins MW, Lovell MR, Sparto PJ. Vestibular rehabilitation for dizziness and balance disorders
after concussion. J Neurol Phys Ther. 2010 Jun;34(2):87-93.
Meehan WP 3rd, Mannix R. Pediatric concussions in United States emergency departments in the years 2002 to 2006. J Pediatr. 2010 Dec;157(6):889-93.
Heitger MH, Jones RD, Macleod AD, Snell DL, Frampton CM, Anderson TJ. Impaired eye movements in post-concussion syndrome indicate suboptimal brain function beyond
the influence of depression, malingering or intellectual ability. Brain. 2009 Oct;132(Pt 10):2850-70.
Eckner JT, Oh YK, Joshi MS, Richardson JK, Ashton-Miller JA. Effect of neck muscle strength and anticipatory cervical muscle activation on the kinematic response of the head
to impulsive loads. Am J Sports Med. 2014 Mar;42(3):566-76.
Tator CH. Chronic traumatic encephalopathy: how serious a sports problem is it? Br J Sports Med. 2014 Jan;48(2):81-3.
McKee AC, Stern RA, Nowinski CJ, Stein TD, Alvarez VE, Daneshvar DH, Lee HS, Wojtowicz SM, Hall G, Baugh CM, Riley DO, Kubilus CA, Cormier KA, Jacobs MA, Martin BR,
Abraham CR, Ikezu T, Reichard RR, Wolozin BL, Budson AE, Goldstein LE, Kowall NW, Cantu RC. The spectrum of disease in chronic traumatic encephalopathy. Brain. 2013
Jan;136(Pt 1):43-64.
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