Sports-Related Concussion
George C. Phillips, MD, FAAP, CAQSM
Clinical Associate Professor of Pediatrics
Sports Medicine Rounds
September 16, 2010
Sports-Related Concussion
• NCAA studies estimated ~ 6% of athletes incurred
a concussion each season (FB)
• More recent studies of high school athletes
estimate a seasonal rate of 15%
– CJSM 2004 McCrea et al
• Sports-related concussions estimated at 300,000
per year
– Over 135,000 in high school sports (JAT 2007 Gessel
et al)
• At least 55,000 to 60,000 concussions occur each
year in high school football alone.
Simple versus Complex Concussion
• Simple
– Resolves in 7-10 days
– No complications
– Formal
neuropsychological
evaluation unnecessary
– Most common form
– Rest until symptoms
resolve
– Graded RTP
• Complex
– Persistent symptoms
– Specific sequelae
• Prolonged cognitive
impairment
– Multiple concussions,
perhaps with less force
– Formal
neuropsychological
evaluation
– Sports medicine
expertise
Classification
• No proposed classification scheme
• Agreement that 80% to 90% of concussions
have symptom resolution within 7-10 days,
except…
• Pediatric concussions may last longer
Are All Athletes Equal?
• CJSM 2007 Iverson
• 114 high school football players
• 52% suffered complex concussions
– No increased history of prior concussions
– Symptoms took an average of 19 days to
resolve (vs. 4.5 days for simple concussions)
Next Steps in Evaluation
• Neuroimaging – no, for clinical purposes
• Balance testing – can see measurable
deficits in first 72 hours
• Neuropsych testing – valid tool; best when
interpreted by an expert
• Genetic testing – unclear value at this time
Return to Play Guidelines
• Stepwise RTP Protocol
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No activity until 24 hours without symptoms
Light aerobic exercise
Sport-specific training (skating, running)
Noncontact training drills
Full contact drills after medical clearance
Return to competition
• Recurrence of symptoms at any stage warrants removal
from participation until symptom-free for another 24 hours.
Participation then resumes one stage earlier in the protocol.
What about Sunday afternoons?
• Team physicians experienced in concussion
management
• Sufficient resources (access to specialists)
• Immediate (sideline) neurocognitive
assessment
• Note: 1 study cited for adult RTP same
day, vs. 7 studies for problems in college
and high school athletes
Return to Play
• Yard EE, Comstock RD. Compliance with return to play
guidelines following concussion in US high school
athletes, 2005–2008. Brain Injury, October 2009; 23(11):
888–898.
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•
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Reviewed use of RTP guidelines at 100 HS
Estimated 400,000 concussions nationwide
AAN guidelines – 40.5% returned early
Prague guidelines – 15% returned early
In football, 15.8% of concussed athletes with LOC
returned in less than 24 hours
Other Management Issues
• Consider depression in the athlete
• Athlete should be asymptomatic, off meds,
for RTP
• Individual consideration for athletes on antidepressant meds and RTP
– Experienced clinician judgment
Preparticipation Screening
• Not just number of concussions, but prior
symptoms
– How good is the concussed athlete’s recall?
• Head, face, neck trauma history
• Impact vs. symptom severity – mismatch?
How Well Do We Take a History?
2008 CJSM Valovich McLeod et al
25
20
15
10
5
0
Head Injury
Knocked Out
Bell Rung or Dinged
How Well Do We Take a History?
2008 CJSM Valovich McLeod et al
Symptom
%(+) Responses
# Episodes
Headache
43.5
3.1 ± 2.1
Dazed or
Confused
Dizziness or
Balance
Problems
Trouble
Concentrating
23.8
2.6 ± 1.8
20.8
2.5 ± 1.8
18.7
3.4 ± 2.1
Duration of Symptoms
• Meehan WP, d’Hemecourt P, Comstock RD.
High School Concussions in the 2008-2009
Academic Year: Mechanism, Symptoms, and
Management. AJSM Preview, August 17, 2010.
• 544 concussed high school athletes
• 15.1% had symptoms > 1 week but <1 month
• 1.5% had symptoms > 1 month
Post-Concussion Syndrome
• ICD-10
– Head trauma w/LOC precedes symptoms by  4 weeks
– Three or more symptoms categories:
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HA, dizziness, malaise, fatigue, phonophobia
Irritable, depression, anxiety, emotionally labile
Subjective concentration, memory, or intellectual difficulties
Insomnia
Reduced alcohol intolerance
Preoccupation with symptoms and fear of brain damage with
hypochondriacal concern and adoption of sick role
Post-Concussion Syndrome
• DSM-IV:
– 3 or more of the following occur shortly after trauma
and last at least 3 months:
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Fatigued easily
Disordered sleep
Headache
Vertigo or dizziness
Irritable or aggressive with little/no provocation
Anxiety, depression, or affective lability
Personality changes
Apathy or lack of spontaneity
Does PCS Exist?
• Plenty of experts say no:
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Depression
PTSD
Litigation, Worker’s Compensation
Chronic Pain
• What are we asking?
– Self-reported questionnaires
– Structured Clinical Interview/Sx assessments
– Neuropsychological testing
• When are we asking?
Attentional Deficits in PCS
• Categorization of PCS patients:
– Mild sustained attentional deficits
• Sustained Attention to Repsonse Task
• Younger, better educated
– Selective and divided attentional deficits
• Best on SART; Stroop Word-Color, PASAT,
Symbol Digits Modality Test impaired
– General attentional deficits
• Poor on everything
• Disproportionately female
Risk Factors for PCS
• Preexisting psychiatric
condition
• Comorbid psychiatric
diagnosis
• Alcohol
• Litigation
• Age
• Female gender
• Violent injury
mechanism
• Dizziness
• Prior head injury or
CNS disorder
• Education
• Learning disability
• Academic success
(GPA)
Post-Concussion Syndrome
• Emotional disturbance and secondary gain
are true confounders of PCS
• Controlled studies reveal objective findings
of cognitive dysfunction in PCS
• Functional neuroimaging and electrophysiology studies can support diagnosis
Episodic Symptoms
• Tucker (1986) described 20 cases with
episodic changes in cognition, mood,
hallucinations
• Abnormal EEG but not epileptiform
• Poor response to antipsychotics, lithium, or
tricyclics (lower seizure threshold)
• Improved with anti-epileptic medications
Episodic Symptoms
• Tinnitus
• Head pain
• Memory gaps for
experiences
• Déjà vu
• Automatisms of
walking and speech
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Staring spells
Anger episodes
Dizziness
Vertigo
Micropsia (funnel of
light)
MIND
• Multiple authors describe similar cases
• Epilepsy Spectrum Disorder (ESD)
• Multiple Intermittent Neurobehavioral
Disorder (MIND)
• No clear etiology
– Hippocampal, brainstem, multifocal cortexwhite matter junction lesions
• Differential: intermittent explosive disorder;
personality disorder; mood disorder
MIND
• Typical neuropsychological profile:
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Mild to moderate attentional problems
Short-term and long-term memory problems
Focal NP deficits matching gross lesions
Frontal lobe dysfunction (olfactory)
Executive dysfunction
Medications for MIND
• No randomized, controlled trials
• Most experience with carbamazepine and valproic
acid
– Both are good for partial seizure disorders
– Carbamazepine used in mood control: rage
– Valproic acid used in mood control: anxiety
• Iowa experience – 95% positive response to CBZ
• Second-line antiepileptics phenytoin and
gabapentin with less experience
Post-Concussion Syndrome
• For athletes, multiple concussions are a significant risk
factor.
• While many symptoms of PCS overlap with other
diagnoses, subscales of symptoms specific for cognitive
function may delineate true cases of PCS.
• Neuropsychological testing can provide objective data for
diagnosis, follow-up comparisons, and information to
assist in reintegrating the injured person to work, school,
and/or athletics.
• If objective neuropsychological findings support the
diagnosis of MIND, a trial of antiepileptic medications
may prove useful.
Multiple Concussions
• 2002 Neurosurgery Collins et al
– History of ≥3 concussions = 9.3x more likely to
experience 3 of 4 “onfield markers”
• LOC, RG amnesia, AG amnesia, or confusion
– 6.7x more likely to experience LOC
• 2003 JAMA Guskiewicz et al
– ≥3 concussions = 3x more likely to have
another concussion
– ≥3 concussions: 30% had symptoms > 1 week
Multiple Concussions
• 2004 Brain Injury Iverson et al
– ≥3 concussions = more preseason symptoms
– ≥3 concussions = 7.7x more likely to have
memory problems 2 days after injury
• 2008 J Ath Train Covassin et al
– ≥3 concussions = significantly slower recovery
of verbal memory and reaction time
– No significant change in symptom scores 5
days after the concussion
Pediatric Concussion
• Zurich guidelines appear applicable down to
age 10
• For younger athletes, need different
evaluation tools, teacher/parent input
• Longer recovery
• Cognitive rest
• “Diffuse cerebral swelling”
• Modifiers may apply even more
Second Impact Syndrome
• Rare, controversial diagnosis
• Results when a second head injury occurs
before resolution of first injury
• Rapid progression to altered sensorium,
seizures, coma, brain death
• Abnormal or immature autoregulation of
cerebral blood flow causes swelling,  ICP
and cerebellar herniation (2-5 minutes)
Chronic Traumatic Encephalopathy
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“Punch-drunk” boxers – Martland 1928
Dementia pugilistica
Psychopathic deterioration of pugilists
Progressive neurodegeneration clinically
associated with memory disturbances,
behavioral and personality changes,
parkinsonism, and speech and gait
abnormalities.
CTE
• 48 cases proven by microscopic evaluation
reported in the literature
• Cerebral and medial temporal lobe atrophy,
ventriculomegaly, enlarged cavum septum
pellucidum, and extensive tauimmunoreactive pathology
– Tau-reactive neurofibrillary tangles (NFT) very
similar to Alzheimer’s disease
CTE
• Football players’ history different from
boxers –
– Younger at age of death (44 yo versus 60 yo)
– Shorter duration of symptoms (6 versus 20.6
yrs)
• Head trauma linked with Alzheimer’s,
suggesting a possible common pathway to
chronic neuronal damage