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 – 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.

• 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 anti-depressant 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

0

5

10

15

20

25

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

23.8 2.6 ± 1.8

Dizziness or Balance

Problems

20.8 2.5 ± 1.8

Trouble Concentrating

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: • 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: • 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: – 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 electro-physiology 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

• 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 cortex-white matter junction lesions

• Differential: intermittent explosive disorder; personality disorder; mood disorder

MIND

• Typical neuropsychological profile: – 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

• “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 tau-immunoreactive 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