4. sport concussions

immediate onset of clinical manifestations

hours-days persistence of DAI clinical manifestations

-> NOT always

NO

focal: laceration, fracture, hemorrhage

diffuse -> force is diffused throughout neurons in form of deceleration or rotation force: concussion

hypotension

hypoxia

cerebral ischemia or edema

oxidative stress

others

severity of secondary injuries

concussion = mild TBI

visible injury/bleeding/skull fracture = moderate or severe TBI

look at slide

the more severe the trauma, the more intense the molecular mechanism will be

concussion + severe brain injury have similar mechanism of neural injury

when brain moves inside cranial cavity, usually force is applied directly/indirectly -> there is damage to neuron fibres

functional mild TBI: no skull fracture or internal bleeding

1- impaired neuronal communication

2- brain nutritional (metabolic) imbalance

3 - excessive inflammation

headache - 85.5%

dizziness - 64.6%

concentration deficits - 47.8%

balance + sleep impairments

behavioural changes

psychological Sx (anxiety, depression)

1st concussion -> 3-4 Sx

2nd concussion -> 5-6 Sx

no 2 identical cases (between AND within subjects)

difficult diagnosis -> Sx disclose 50% + no valid test

crucial first 48h -> Sx can come/go

20% -> 1st Sx 12-48h post trauma

# & Intensity of symptoms ≠ Severity or Recovery

majority of S resolve in 10-14 days

5-30% PCS = Sx at rest or upon min exertion

64.3% -> 1-7 days

% goes up with age and female>males

but is Sx recovery really recover?

1 - concussive event

2 - acute

- impaired: elevated Sx, functional impairments, physiological dysfunction

- clinical recovery

3 - post-acute

- compensatory: full clinical recovery, persistent physiological dysfunction (no Sx)

- physiological recovery (common time for return to play)

4 - full

- complete: full clinical recovery, normal physiological function

- full clinical + physiological recovery

history of concussion: 1st concussion increases risk of 2nd by 3-5x

women: thinner cranium, weaker neck muscles, hormonal differences, self-report biases

kids: weaker neck muscles, sensitive neurons, brain development disruption, worst consequences of injury

1 - protect the player -> take them out

- continued competition increases recovery time

2 - document the incident

- signs + Sx, direct vs indirect, details

3 - inform parents if minor

- follow up on Sx for first 48hrs, avoid anything that could hide Sx (I.e. sleeping, anti-inflammatories)

4 - get medical appointment to clarify diagnostic

- only MDs can diagnose

5 - if not diagnosed -> progressive return to normal life

if diagnosed -> concussion management protocol

loss of consciousness, vomiting, speech, tingling, double vision, seizures, severe balance issues....

1 - complete rest

- duration: at least 48h but not more than few days, too much rest can have negative effects

- reduce mental stimulation to a minimum

2 - return to learn/work

- intellectual activities should resume before any PA

- must be able to study for 45 mins at home

3 - PA

- impossible to return to play in <7d if followed

- if Sx return, rest until resolved, resume at PREVIOUS step

look at slides for exact protocol

persistant Sx (>4wks) + 2nd concussion in same season -> end current season, take all time to recover

3+ concussions + PCS -> change to lower risk sport

more concussions = more risks of permanent deficits

peaches, parents, athletes, organizations, public

quitting a sport can be extremely difficult

- don't be judgemental

- social activities

- help them find a lower risk one

remember

- athletes are scared to let down people

- sport is part of their identity

sportsmanship (no violent behaviours)

disclose concussion Sx

follow return-to-play protocol

support concussed teammates

get informed

install sportsmanship culture

minimize contact drills

teach appropriate contact techniques

get informed

educate those around you

favour healthy communication

discuss consequences of violence behaviours in sport

enforce respect of game rules

install sportsmanship culture

educate coaches + referees

adapt game rules to favour safety

change sport culture

stop cheering violet actions

reward efforts over results

dismiss warrior mentality

progressive neurodegenerative disease caused by repetitive head trauma

diagnostic feature: abnormal accumulation of Tau proteins around brain vasculature, can only be diagnose after death w/brain autopsy

manifestations:

1- mood changes (depression)

2- behaviour changes (aggression, impulsivity)

3- cognitive deficits (attention, memory)

CTE is caused by repetitive hits to head over period of years -> doesn't mean handful of concussions

FALSE - only 10-20% of concussion involve amnesia or LoC

false - used to protect against moderate + severe TBIs, protect teeth + jaw

true - current ones are unreliable

false - recovery is independent of strength of impact and of the # or intensity of initial Sx, no way to know

true - long term if player exhibit more sportsmanship and min frequency of violence

false - short term exposure to contact is what matters

• Concussion = mild TBI

Great for case identification in research and

streamlining care in clinical setting

Diagnosis ≠ predictor of clinical outcome

Next step: Working on more granular severity scale based on miltidimensional biomarkers to replace the ‘mild’ label

Disallowing body checks in youth ice hockey and restricting collisions in football practices significantly reduced the rate of concussions

Mouthguards were associated with a 28% decrese in concussion rates in ice hockey

Implementation of concussion management protocols is associated with reduced recurrence of concussions

Immediate removal and sideline assessments if any of the clinical signs discussed prior- LoF, Amnesia, Neuromotor, etc.

Sideline multimodal assessment should take at least 10-15 minutes

- Symptoms, gait, balance, cognitive functions- Use of Sport Concussion Assessment Tool (SCAT) valid within first 72 hours

Re-evaluate within hours and days whether concussion is confirmed or suspected

First 48h: Strict rest = Bad / Relative rest = Good

- Relative rest = Relaxed daily living & minimal screen time

- No ‘dark room’ / less cocooning

Days 2-10: Resume no-contact, low intensity PA- Subsymptom aerobic exercise reduces risk of persistent symptoms & recovery time

- Increase intensity gradually pending no significant Sx exacerbation- Same for light cognitive activity- Sleep disturbances associated with persistent Sx

Caveat: Data from athletic population. Non-athletes may require more rest

Specialist referral warranted for treatment of targeted persistent Sx (>4 weeks)

- Ex.: Cervicogenic symptoms, migraines, balance impairments, etc.

- Individualised & Multidisciplinary approach is best - MD, RN, OT, PT, Kinesiologist, Chiropractor, Psychologist and Neuropsychologists

Sx associated with concussions are often non-specific - Could be caused by something else (ex.: comorbidities, medications)

- Could have been present prior and exacerbated by the concussion

Normal recovery = <4 weeks

- 4+ Weeks = Persistent Symptoms warranting closer management

- Beyond 4 months = Persistent Concussion Syndrome (PCS)

Predictors of prolonged clinical recovery

- Best Predictor = Sx # & Intensity few hours post-impact- Genetic Vulnerability for incidence & complicated recovery: APOE4

- Delayed access to HCP- Continued play despite Sx

Advanced MRI tehnologies (DTI) can notice microstructural damages and recovery where conventional MRIs cannot

- Further research required for validation

the motion of water molecules around neurons

93% RTL within 10 days

- No sex differences and minimal age differences- Gradual return to cognitive activities (pending no Sx exacerbation) associated with better recovery and minimal impact on school performance- Students should work in more frequent but shorter sessions spaced by breaks

- Reasonable accommodations favour recovery and reduce stress (ex.: postponing tests)

look at slide there is a table w/steps

Can occur in parallel with RTL but not at same speed

- Full RTL must precede full RTS- Begin step 1as soon as 24-48-hours post-injury (no cocooning!)

- At least 24h between each steps- Steps 4-6 should be monitored by HCP

look at slide there is a table w/steps

Compared to general populations, studies of former athletes (pro and amateur) found:- No significant increased incidence in depression, suicidality, cognitive impairments and neurodegenerative diseases- Difference in mortality rate from dementia and neurological disorders (ex.: ALS)

- Caveat: Limited studies with high-quality data

Unable to adjust for many confounding variables

Same for causal link with CTE: unclear due to limited high-quality studies

- Multiple head impacts is obviously not good but how many is real bad?

No clear evidence or factor that would justify immediate and unequivocal discontinued participation in contact or collision sports.

Should be a continuous discussion considering multiple variables between athletes, HCPs and other stakeholders (SBNH!)

Ex.: Para-athlete with shortened lifespan

Given the positive benefits of exercise on health, all athletes who ultimately retire from contact or collision sports should be encouraged to continue non-contact or low-contact PA.