Concussions Flashcards
What is a concussion?
traumatic brain injury caused by a direct blow to the head, neck or body resulting in an impulsive force being transmitted to the brain.
Initiates a neurotransmitter and metabolic cascade, with possible axonal injury, blood flow change and inflammation affecting the brain
What are different methods of concussion impact?
direct contact
inertial contact (acceleration
Shear forces caused by rotational acceleration is the primary predominant mechanism of concussions
How is a concussion mechanism determined?
by amount of mechanical energy from acceleration transferred to the brain and vascular tissue
Linear acceleration average concussive head impact 29.7g
What is the physiology of a concussion?
Neurotransmitters are released and influx of ions ==> binding of glutamate to excitatory amino acids receptors ==> leads to further neuronal depolarization with efflux of potassium and calcium ==> the Na-K pump works in overtime to try to restore neuronal membrane ==> requires increased use of adenosine triphosphate ==> increase in glucose metabolism + diminished cerebral blood flow = cellular energy crisis
What is the role of Calcium in concussions?
Impairs mitochondria and ATP production
Calcium accumulation can directly activate pathways leading to cell death
has been shown to impair neural connectivity
Seen within hours and may persist for 2-4days
What is metabolic vulnerability?
Following concussive episodes, studies have shown changes in brain metabolism.
Evidence linking severity of brain injury and recovery with extent of ATP and N-acetylaspartate (NAA) decrease and recovery
How long did it take for NAA levels to return to normal in studies?
Brain concentration of NAA remained profoundly depressed in 21/40 concussed athletes at 22 days but returned to normal levels at 30 days
recovery is an exponential phenomenon
What is second impact syndrome?
repetitive head injury syndrome
Condition in which a person experiences a second head injury before the complete recovery of the initial injury
Often leading to death
Results from dysfunctional cerebral blood flow autoregulation leading to increased intracranial pressure
Herniation= rapid pressure develops and deterioration and leading to death within 2-5min
How could we prevent concussions?
Neck strength only plays a role to a certain extent
Ability to actively engage neck muscles and resist linear and rotational acceleration is more important
Helmets: may reduce concussion severity and duration of symptoms as well as SRC odds if direct head impact
Mouthguard: conflicting results
Should you refer a concussion to a physician?
All concussions should ideally be referred to a physician who has experience managing sport-related head injuries
A referral to a physician is required for all concussions with symptoms lasting more than 10 days
What are persistent concussion symptoms?
up to 30% of people experience persisting post-concussive symptoms
5th CCS defines persisting post concussive symptoms as symptoms lasting 2 weeks or longer for adults and 4 weeks or longer for children
Frequently associated with mental health problems, declines in QOL and difficulties returning to sport, school work and ADLS
What are risk factors for concussion outcomes?
Increased deficits and protracted recovery:
history of concussion
history of migraine
Diagnoses of learning disability
Sex (females)
Age (younger)
What does the SCOAT6 include?
Symptoms, cognitive recall, blood pressure measures, cervical evaluation, neurological exam, timed tandem gait, modified VOMs
What are the concussion clinical trajectories?
Vestibular
oculomotor
cognitive
post-traumatic migraine
cervical
anxiety/mood
What is the cognitive/fatigue trajectory?
S/S: fatigue, decreased energy levels, non-specific headaches, sleep disturbances
Common to see symptoms increase at end of day
difficulties concentrating
increase in headache with cognitive activity
Neurocognitive testing typically reveals mild global deficits in memory, processing speed and reaction time
What is the vestibular trajectory?
S/S dizziness, fogginess, nausea, feeling of being detached, anxiety, overstimulation in more complex environments
increase in symptoms in busier, more stimulating environments
Rapid head or body motion may exacerbate symptoms
Assess via a comprehensive vestibular/ocular motor screening
What is the Ocular motor trajectory ?
S/S localized, frontally based headaches, fatigue, distractibility, difficulties with visually based classes, pressure behind eyes, difficulty with focus
difficulty with extended time in front of computer screen or reading
Characterize headaches
most likely the ocular motor dysfunction will be evident with near convergence and/or accommodation measurements
What is the anxiety/mood trajectory?
S/S: increase in anxiety, including ruminative thoughts, hypervigilance, feelings of being overwhelmed, sadness, and/or hopelessness
report sleep disturbances with inability to quiet minds or stop thinking and worrying
symptoms may manifest through headache, fogginess, dizziness, or fatigue
Some vestibular dysfunction testing may provoke symptoms (must be treated before treating anxiety)
What is the post migraine trajectory?
described as unilateral moderate-to-severe intensity headache following a head trauma with a pulsating quality that is associated with nausea and photosensitivity and/or phono sensitivity and is often aggravated by physical activity
Exacerbated by stress, sleep dysregulation, anxiety or emotional changes, dietary trigger
What is the cervical trajectory?
S/S headache and neck pain
Important to focus on characterization of headache as well as location
Ask about onset and course of ADL to help determine triggers
Assess cervical spine for ROM, strength, instability tests and flexibility of musculature
What are the different components of VOMS?
Smooth pursuits
Saccades
Near point convergence
VOR
VMS
What are some tests to determine if C/S causing headache?
Smooth pursuit neck torsion test
Cervical joint position error test (target laser)
Flexion rotation test (45 degrees rotation)
What is Benign Paroxysmal positional vertigo?
Benign: non life-threatening
Paroxysmal: comes in sudden brief spells
Positional: triggered by certain head positions
Vertigo: false sense of rotational movement
What is the hallpike-Dix test?
Patient long sitting with head rotated 30-45 d
Therapist holds head and patient is then assisted into supine position with head slightly below horizontal plane and position maintained for 30-60sec
