WK4 - Head Injury Recognition and Management Flashcards
(162 cards)
1
Q
How many athletes admitted to continue playing after being hit in the head?
A
30%
2
Q
What % of athletes had knowledge of concussions and the complications of head injuries?
A
43%
3
Q
What percentage of athletes sought medical clearance for RTP? And what % returned to training?
A
34%
25%
4
Q
What percentage of players felt that time off for rehab was too long?
A
75%
5
Q
What is the past definition of a ‘concussion’?
A
A clinical syndrome characterized by immediate and transient post-traumatic impairment of neural function (altered consciousness, vision or equilibrium), any trauma-induced alteration in mental status that may/may not include loss of consciousness.
6
Q
What is the current definition for ‘sport-related concussions’?
A
-Evolving injury
-Acute change rapidly based on clinical signs and symptoms which may reflect underlying physiological injury in brain
-Impairment of higher cerebral function
-Considered one of most complex injuries to diagnose, assess and manage
- Potential for further harm
7
Q
What considerations are made for ‘sports-related concussions’?
A
whether it is the acute damage or is it the aftereffects of the damage
whether it is the concussion part of TBI spectrum with lesser degrees of diffuse structural change that are typically seen in TBI OR due to the result of reversible physiological change?
8
Q
List the characteristics of sports-related concussion.
A
- evolving injury
- acute: change rapidly based on clinical signs/symptoms that may reflect underlying injury in brain
- impairment of higher cerebral function
- considered among most complex injuries in sports medicine to diagnose, assess and manage
- potential for further harm
9
Q
Define sport-related concussion.
A
the rapid onset of short-lived impairment of neurological function that resolved spontaneously
- could be mins or hrs –> require followup
10
Q
Effects of Sports-related concussions.
A
May result in neuropathological changes but acute clinical signs and symptoms largely reflect a functional disturbance rather than a structural injury.
- no abnormality is seen on standard structural neurimaging studies
11
Q
What are physiological characteristics of the brain?
A
- one of softest biologic materials
- resistance to changing shape (viscoelastic) when slow or transient pressure is applied BUT can deform easily from shearing forces
- Shear modulus of brain tissue is several orders of magnitude lower than Bulk modulus of brain tissue
- differing mechanical properties of grey and white matter (Water Hammer theory)
12
Q
If head is constrained to exclude any rotational motion, it is difficult to produce traumatic unconsciousness. True or false and state why.
A
TRUE
angular acceleration (rotation) of head can cause axonal injury in brain proportional to degree of coronal plane –> doesn’t necessarily need impact
13
Q
What 2 components happen in nearly every concussion?
A
linear and rotational acceleration
14
Q
Define Young’s Modulus.
A
measures resistance of solid to a change in its length
15
Q
Define Shear Modulus.
A
measures resistance of motion of planes within a solid parallel to each other
16
Q
Define Bulk Modulus.
A
Measures resistance of solids or liquids to changes in their volume
17
Q
Why are there differing mechanical properties of grey and white matter?
A
- repeated blows to head may distribute forces through incompressible CSF
- causes shear forces at intersection between grey and white matter, possible breakdown of blood-brain barrier and haemorrhage
18
Q
What is the Water Hammer Theroy?
A
The region of brain exposed to highest force is base of sulcus where “water-hammer” force must dissipate if brain integrity is retained
- causing haemorrhage at angles (leaves iron behind)
19
Q
Why do white/grey matter affect forced applied to brain?
A
Differing rigidity features of grey and white matter result in shearing at intergace as non-compressible CSF is driven into sulci
20
Q
Difference in normal vs female soccer player brain volume?
A
Brain volume in normal women increases 2-3% or remains the same but female soccer players were experiencing increased sulcal volume even without concussion (just from forces)
21
Q
Concussion can occur with or without loss of consciousness. True or false.
A
True
22
Q
What is the proximal cause of diffuse brain injury in general and concussion?
A
Rapid rotational loading of head and neck about craniocervical junction and torso
23
Q
What to do when concussive incident occurs on field?
A
Recognise - signs
Remove player from field/play
Rest
Refer them to Dr
Risk Reduction
RTS
Keep calm and watch the game.
SIDELINE EVALUATION!!!
24
Q
What is the importance of recognising injury and mechanisms? e.g. from sideline evaluations
A
- I should know if athlete is behaving abnormally from observing the game.
- assessment of symptoms
- cognitive and cranial nerve function
- balance
- serial assessments
25
What is the Glasgow Coma Scale designed for?
for people in hospital to monitor those with severe head injury, want to achieve a 15.
26
What are the 3 categories of the Glasgow Come Scale?
Eye opening
- spontaneous 4
- to loud voice 3
- to pain 2
- none 1
Verbale response
- oriented 5
- confused, disoriented 4
- inappropriate words 3
- incomprehensible sounds 2
- none 1
Best motor response
- obeys 6
- localised 5
- withdraws (Flexion) 4
- abnormal flexion posturing 3
- extension posturing 2
- none 1
27
Explain the process of NRL Removal from Play.
Player must be immediately removed from play with any of the following observations by an Club staff member, whether observe directly or indirectly.
28
What is Cat1 of the valuation for determining concussion?
Must leave field and cannot return as there is indication of higher brain function
- loss of consciousness
- no protective action while falling to ground
- impact seizure or tonic posturing
- confusion, disorientation
- memory impairment
- balance disturbance
- dazed/blank/vacant stare or not normal selves
- behavioural change atypical of player
29
Why is 'no protective action while falling to ground' part of the Cat1 of evaluating concussion?
no effect to protect themselves means they were most likely concussed at the time of impact
30
Why is 'impact seizure or tonic posturing' part of Cat1 of evaluating concussions?
- hyperactivity of brainstem, NOT epilepsy
- immediate sequelae of concussive brain injury
- legs extended, arms in bear hug position, spasming and jerking
- potentially due to facial contact, activating afferent pathways of physiological mechanisms.
e.g. diving reflex - submersion in water activates reflex, resulting in decreased HR
31
What are the characteristics of the 'Fencing' response?
- no protective action during fall to ground (indicates magnitude/localisation of impact)
- resembles asymmetrical tonic neck reflex in human infants
- mechanical forces of sufficient magnitude on midbrain to elicit a fencing response (caution in guiding RTP)
32
Meaning of mechanical forces in 'fencing' response.
Mechanical forces to head may stretch cerebellar peduncles and activate LVN
- means that a lot of torsion loading on neck going through brainstem which was sufficient enough to cause this response
33
What is Cat2 of the evaluation process of concussions?
Requires immediate removal from play for further assessment (may still be able to RTP)
34
List characteristics of Cat2 of the Evaluation process of concussions.
- loss of responsiveness (player motionless for 2-3s/until support staff arrive
- possible tonic posturing or impact seizure
possible balance disturbance directly observed
- SCAT 5 carried out
35
What is the Maddocks Score test?
memory test - ability to recall and also form new memories, indication of higher brain functioning
36
When is the Maddocks score used?
Only validated for sideline diagnosis of concussion only and is not used for serial testing
37
What questions are asked in the Maddocks Score test?
What venue are we at today?
Which half is it now?
Who score last in this match?
What team did you play last week/game?
Did you team win the last game?
38
What is the Balance Error Score System (BESS)?
most commonly used low-technology balance assessment for those with sports-related concussion
Require pre-test scores to know how athlete normally performs on the test
Process:
- standing within square with feet together, hands on hips and eyes closed
- hold for 20s, numbers of errors are observed.
39
What are the errors in BESS?
- lifting hands off iliac crest
-opening eyes (when inappropriate)
- stepping, stumbling or falling
- moving hip more than 30deg of FLEX or ABD
- lifting the forefoot or heel
- remaining out of the testing position for more than 5 seconds
40
What is the Tandem Gait Test?
assesses balance and stability through movement, can be used during medical clearance for RTP
- Suspected concussed athlete walk 3m along straight line using alternate heel-toe gait, turn, and return to starting as quickly as possible
- 4 trials done, best retained
- Should be completed in 14 seconds
- Fail if step off line, separation between heel and toe, touch/grab examiner or an object to stabilise
- Can be used together with another concurrent memory test – etc reciting months of the year
41
What is the Sway Test?
Measures static balance
- out of 100
- perfect = 100
42
Effects of concussion...
cause balance problems by adversely affecting either NCS or inner ear balance mechanism
dizziness can be a variety of reasons
e.g. vestibular, visual, cardiovascular
43
Define epidural hematoma.
- arterial blood, life threatening
- very rapid, within an hour or 2
- dura peels off skull, blod placing pressure on brain
44
Define subdural heamtoma.
- venous blood, will be slow and may not present for a while
- dura attached to skull
45
What happens if there is clear diagnosis of brain injury or concussion?
NO RTP!! and SCAT5 required.
SCAT5 required to be cleared to play after removal from play
46
What is the theory of the consequences of concussions?
Repeated trauma to head could cause damage to microtubules --> release of tau proteins which clump together and find their way into damaged structures of brain.
Similar to those seen in late-stage Alzheimer's patients but in different brain areas
47
List some characteristics of the consequence of concussions.
- tends to accumulate in emotional brain - memory stage
- behavioural symptoms
- thalamus is the region that undergoes changes to repeated head injury
- psychopathic deterioration after multiple repeated head injuries (1 dose may not cause this damage)
- 1-2 concussions = 1.5x more likely to suffer depression
- >2 = more likely to suffer depression, cognitive deficits, memory problems and earlier onset of Alzheimers
- chronic traumatic encephalopathy
- reinjury implications
48
What are the effects of concussion on behaviour symptoms?
- emotional lability, aggression, violent outbursts
- due to anatomical regions associated with emotions being damaged due to concussion
- repeated damage could lead to long-term issues
49
Explain the neurophysiology of a concussion.
trauma = excessive extracellular K+
--> increased demand for glucose followed by marked metabolic depression which can take weeks to resolve
50
Explain the cascade of injury-induced concussions.
dramatically alters cell env where neighbouring cells that are not directly and irreversible damaged are rendered extremely vulnerable to secondary insults (2nd impact/head injury)
= compromises ability to exhibit therapeutic plasticity
* consider more recovery time if recurring head injuries are present
51
Persistent Post-Concussion Symptoms (PPCS).
SYmptoms persist for >2wks after initial insult in adults and >4wks in children
- dizziness/fatigue etc
Understanding cause of symptoms can help attain treatment
52
Why do we get PPCS?
Heart is innervated by both thoracic (CNS) and by the head (PNS)
- Injury to head may interfere with PNS
- Upsets balance between CNS and PNS
- Autonomic dysfunction could explain why head injuries cause ongoing issues
* Concussion could damage parasympathetic nervous system
* Affects homeostatic balance
* PNS and SNS don’t align properly, improper responses due to autonomic dysfunction
* Eg. HR does not respond appropriately to exercise/standing up really quickly feel dizzy as a response
53
Why do we get PPCS?
Heart is innervated by both thoracic (CNS) and by the head (PNS)
- Injury to head may interfere with PNS
- Upsets balance between CNS and PNS
- Autonomic dysfunction could explain why head injuries cause ongoing issues
* Concussion could damage parasympathetic nervous system
* Affects homeostatic balance
* PNS and SNS don’t align properly, improper responses due to autonomic dysfunction
*Eg. HR does not respond appropriately to exercise/standing up really quickly feel dizzy as a response
54
What is orthostatic hypotension?
- low BP and lightheadedness
- may be useful tool to judge their RTP
55
What is the importance of HR variability?
- greater HRV suggests that ANS is appropriately responding to requirements of the environment
- lower HRV - ANS not modulating HR as efficiently
- amygdala is believed to be major efferent source of modulation of autonomic, endocrine, and cardiovascular response (look into HRV devices - even HR monitor)
56
Why is sleep importance for recovery of concussion/head injuries?
Brain recovers during sleep by rinse Cycle (stage 3 non-rem sleep)
- opens up channels (similar to lymphatic systems since brain doesn't have lymphatic system)
- drop in norepinephrine/adrenaline - biggest increase in growth hormone (for recovery)
- Cx spine is attached to brain - responsible for noradrenaline/adrenaline could be disrupted by concussion.
If can't sleep...
- can't get good cleaning process of brain
- disturbance of circadian rhythm
- hard to recover as waste clearance can't occuring during sleep
Normalisation of sleep is important
57
What does ARL say to head injuries?
Under no circumstance should the player be allowed to continue playing or RTP during same game.
- eliminates potential 2nd hit syndrome and potential liability (cascade of events due to consecutive head injuries)
58
Explain SCAT5 for assessing head injury.
Not diagnostic
- event if they pass SCAT, could still have concussion
- consider patient in totality (DRABCD, 9 signs of concussion)
evolution of symptoms
59
Explain SCAT3 for assessing head injury.
standardised tool for evaluating injured athletes for concussion and used in athletes aged >13y
children <13y, use child SCAT3
designed for use by medical professionals
- pre-season testing can be useful for comparison to post-injury assessment and injury interpretation
60
What is the importance of safety protocol for concussion injuries?
have safe removal plan for injured athletes, paying attention to possibility of neck trauma
61
How are concussions evalutated?
Post-traumatic amnesia
- stuff they should regocnise
- e.g. girl, dog, football
- can also tell them random facts and see if they can recall it later
Retrograde amnesia
- ask them what happened in the game/past
Eye movement
- King-Devick Test can capture impairment of eye movements, attention, language and other areas that correlate with suboptimal brain function
Balance Test
62
What else do we need to consider in acute assessment of concussion/head injury?
BALANCE!
- heel to toe
- dominant foot to rear
- hands on hips
- eyes closed and test for 20s
- 5 errors suspect concussion
63
What happens after the athlete is symptom-free at REST?
a graduated aerobic exertional test to examine for return of symptoms
When asymptomatic after exertion then consider neuro-psych testing to compare baseline scores
64
List an example of a graduated aerobic exertional test.
Buffalo Test
- athletes with post-concussive symptoms were placed on treadmill to do aerobic exercise and assessed on when they felt their symptoms com one
- corresponding pulse rates would be their "threshold" for RTP/training
65
Clinical symptom resolution may not always coincide with physiological recovery. True or False.
TRUE!
- generates a hidden window of cerebral vulnerability with heightened risk for 2ndary injuries
66
What are the implications of impaired cerebral vasoreactivity despite symptom resolution in SRCs?
- increased risk of later-life neurodegeneration and dementia if you tried to go back too early
- cereberal vasoreactivity (CRV) = measure of hemodynamic reserve
- CRV is impaired as early as 4days and remains impaired up to 3 months post-injury despite symptom resolution
67
Just using symptoms alone is accurate enough to determine whether they have a concussion or not. True or False
FALSE!
- Ex alone can bring about concussion-like symptoms even if they don't have concussions
e.g. dizziness, vomiting, fatigue
68
What are the RTP Guidelines?
Athlete should complete the following...
1. removal from contest if signs/symptoms of concussion
2. no RTP in current game
3. medical evaluation after injury
- RULE OUT MORE SERIOUS INTERCRANIAL PATHOLOGY
- neuropsychologic testing considered cornerstone of proper post-injury Ax
4. stepwise RTP
5. NO ACTIVITY AND REST UNTIL ASYMPTOMATIC
- light aerobic Ex
- sport-specific training
- noncontact drills
- full contact drills
- game play
69
NO activity and rest until asymptomatic. True or False.
TRUE!
- just giving little bit of Ex may be adjunct towards helping brain settle down
- generate response to RTP
70
What is considered in a neuropsychological Ax?
- processing speed = indicator of brain efficacy
71
What should we have in our neuropsychological Ax? e.g. what we want to see
Rapid brain processing of info for selection and initiation of response and generation of properly coordinated muscle forces
Simple reaction time
- e.g. drop test
Choice reaction time
- e.g. only go when light turns green
72
Limitations of neuropsychological Ax.
Computer-assisted tests
- can assess athlete's RT accurately?
Not specific to sports
- just a screen doesn't necessarily translate to making decisions during training/competition
73
What is the relationship between years of football playing experience and NCRT (neurocognitive RT) as well as L hippocampus volume?
Inverse association
- Subtle adverse effects of concussion on cognitive function shown to persist for as long as 7 years
- Abnormalities in neurocognitive and neurophysiologic processes related to vision have been found to result from concussion, as well as repetitive blows to the head that do not produce clinical symptoms
74
What is the evidence between years of football playing experience and NCRT (neurocognitive RT) as well as L hippocampus volume?
- Athletes who sustain concussions subsequently sustain over 2x as many MSK injuries as other athletes
- MSK injuries can affect neurocognitive results among athletes who haven’t sustained concussion
75
What happens when white matter is damaged (Corpus Callosum)?
- decrease interhemispheric connectivity
76
What capability is limited when concussion/head injury occurs?
- capability to protect joints through rapid generation of muscle stiffness in response to perturbation
77
What affects postural balance in the neuromechanical responsiveness cycle?
visuomotor reaction time
muscle strength and endurance
78
What affects visuomotor rRT in the neuromechanical responsiveness cycle?
brain processing of neural input
79
Brain processing of neural input and reflexive muscle responses affect each other in the neuromechanical cycle. True or False?
TRUE
80
Multi-segmental alignment and reflexive muscle responses do not affect each other in the neuromechanical cycle. True or false?
FALSE! They do affect each other.
81
What affects muscle strength and endurance in the neuromechanical responsiveness cycle?
multi-segmental alignment
82
Why is there an elevation of MSK injury after a concussion?
- altered function connectivity between partially separated brain areas after concussions has been documented among individuals with normal clinical test results.
BUT connectivity is not there yet, needs to be functional!
83
What does hyperconnectivity appear to be?
- appears to be a compensatory response
84
What are the effects of concussion?
- elevates risk for MSK injury
- identified through specific dual-task screening tests
- other approaches may enhance neuromechanical responsiveness including balance training with cognitive/visual challenges.
85
What % of mild traumatic injury patients reported post-traumatic vision or oculomotor problems? And what % was reported from patients with SRC?
30-60%
30%
86
What are the effects of concussion related to vision?
- oculomotor-related outcomes after SRC involves converge insufficiency
- abnormal near point of convergence in eyesight
- higher cerebral not functioning properly
- cannot concentrate on things (bad for students!)
- 45% athletes experienced after SRC
- can be used as RTP test
- patients with CI endorse more concussion symptoms compared with those with normal vision.
87
How to assess vision as part of RTP test?
- bring pen to face (>5cm from face, 45% athletes with SRC had convergence insufficiency - don't seen it till its further away)
- at what point do they see double vision
88
What regions of the brain act as the neural basis for RT/processing speed and oculomotor control?
- cerebellum
- brain stem
- diencephalon/midbrain
- aspects of cerebral cortex
89
What are the biomarkers of concussions?
- not really available yet
Products released by damaged tissue
- astrocyte-specific proteins
- several neuron-specfic proteins
- oligodendrocyte-specific proteins
- GFAP (Glial Fibrillary Acidic Protein)
90
What is the role of GFAP?
intermediate protein responsible for maintaining mechanical strength
91
What is the role of NF-L?
intermediate filament found predominantly in myelinated axons
Not meant to be in bloodstream --> body produces antigens to this
- people may develop CTE over time
- body produces antibody (because NFL seen as antigen/produces antigen) against own brain
- damage over time
92
If head injury/blood-brain barrier occur and NF-L is present again, it may accumulate over time. True or False?
TRUE!
93
How to manage concussions?
Manage actively > complete rest
- improve autonomic dysfunction, cognitive issues, HRV
- performing mild cognitive task during recovery eliminated differences in HRV between concussed and control groups
- cognitive tasks as early as 4days after injury may help improve AND function nad expedite return to learn
94
What medications are use in concussions?
Valprioc acid - epilepsy drug could treat some biomarkers
- elevation in GFAP (peak within 24h and return to baseline) and NFL (peak within day3, remain elevated at day) can be seen within 2h after injury
- VA results in significant lower GFAP and NFL levels (biomarkers of concussions)
95
What can be done to reduce concussion injuries?
- avoid head knocks undergoing reflex training, provide tools to improve RT (e.g. boxing)
- mouthguard
- headgear
96
How do mouthguards reduce head injury risk?
- uppercut transmits forces through temporomandibular joint to brain
- BUT most head injuries are due to rotational forces through midbrain which challenges viscoelasticity of cerebral hemispheres
- reduced upprcut blow only reduces forces slightly
97
How does headgear decrease head injury risk?
1. could slightly reduce water hammer effect BUT could weigh head down more
2. gender disparities (heavier for females in proportion to their neck)
3. increase alertness and improve RT
4. no design offers protection in all types of impact
5. absorption of rotational force and translational force and velocities of impact are different depending on design
6. reduce skull injuries (may not for concussions)
7. does not universally protect against head injury
98
Policy eliminates body checking in youth ice hockey - 67% reduced risk of concussion in 11y-12y hockey players. True or False?
TRUE!
evidence supporting future research from ice hockey, basketball and rugby examining mouthguards in contact sport where meta-analysis suggests there is a 19% reduced risk of concussion
99
What are concussion risk factors/modifiers?
1. number
2. symptoms >10days
3. concussive convulsion
4. temporal history
5. threshold
6. age >18y
7. migraine Hx
8. mental heatlh
9. A.D.D
10. learning disorders
11. style of play
100
Sports-related accidents constitute 3rd most common cause of spinal cord trauma. True or False?
False.
Its the 4th!
101
Sports-related accidents are the 2nd most frequent cause of spinal cord injuries for those <30y. True or false?
True!
102
What % of patients with head injury also have Cx spine injury?
10-20%
- often go together, always just assume one comes with the other
103
What % of patients have a missed/delayed diagnosis for Spinal cord injuries?
17%
104
Females with concussion-related ED visits between 5-49y had higher rate of comorbid neck injury than males across all injury contexts. True or False?
True
105
Neck and head injuries can have similar symptoms and frequently occur together. True or false
TRUE
106
List a few characteristics of the Cx spine.
anatomically complex, essential roles are to orient head and sensory system and protect spinal cord.
107
What is providing resistance to bending of the spinal column?
- architecture of individual bones stacking together
- muscles
- ligaments/connective tissue
108
Explain the male vs female anatomical variation of the spine.
- C2-C7 in males have increased A-P dimension
- vertebral body to spinous process length was greater in males from C5-C7
- important factor with regards to loading, column mechanics and stability
109
Where/how does the load come down/distributed in the spine?
- distributed between vertebral body and facet
- VB is huge compared to facet in Lx spine but not in cervical
- studies identified primary role for facet joints in compressive stability of Cx spine
110
How much load can the facet joints hold?
contributes as much as 55% of load carrying capacity at higher loads
joint congruency --> stability (bony stability contributes 20% of stability compared to 80% from muscles.
111
What are the characteristics of the lordotic curve?
* Facet joints anatomically lined up
* Loss of cervical lordosis (movement into kyphosis) causes elongations of the joint ligaments by 73% at C5-6 level compared to elongations sustained in normal lordotic spine
- Loss of natural absorption puts vertebral bodies at risk
112
Repeated minor neck juries leads to pathological changes in CS. True or false?
true
113
What is neutral spine position?
* Normal lordotic curve
* Forces transmitted to head are dissipated in cervical muscles and ligaments
The 3 positions
- lordosis, straight, kyphosis
114
What is the threshold of the spine?
200N
Total force transmitted by each front-row (in rugby scrum is approx. 7000-9000N
* Hooker bears up to half of this total load
* Combined force of opposing forward packs on engagement is close to 15000N
115
Effect of rugby/sumo/other sport on forces applied/experienced.
-Huge initial impact forces on engagement
-Combination of axial, sheer and rotational forces on neck (cervical spine)
* Not just a single load
In American football players, 60% showed loss of physiological cervical lordosis due to continued cervical loading
81% of Sumo wrestlers showed loss of lordosis (out of 53 in a study)
116
75 1st Year football recruits who underwent x-rays of their Cx spine after playing football in high school but before playing in college.
What did this study find?
32% had 1 or more of...
- occult fractures
- vertebral body compression fractures
- intervertebral disc space narrowing
- other degenerative changes
13% admitted to previous history of neck symptoms
Axial loads could not be dissipated by neck
117
Which part of Cx spine had greatest joint angle (deg) during pre-engagement of a rugby scrum? and which part during engagement
C4-C7 - pre
Head-C2 - engaged
118
Scrum that breaks = more neck injuries. True or False
TRUE
119
Potential for repeated minor neck injuries to lead to pathological changes in cervical spine. True or false
TRUE
120
Explain the effects of soccer on spine.
- Onset degenerative changes occur 10-20 years earlier than age match controls (those who didn’t play soccer) + increased frequency in males
- Due to high-impact and/or low-impact recurrent trauma to CS caused by heading the ball
* Incremental, not a one-off event
121
Effect of sumo wrestling on spine.
-42% had deformity of cervical bodies (mainly c3 and c6)
122
List neurophysiological aspecst of prevention.
-Reflex muscular activity of trunk muscles are responsible for ~40% of maintaining stability when facing postural perturbation
-Latent time after sudden acceleration is slightly longer for men than women, even longer with age increase
* More difficulty in sustaining neurophysiological reflex
-Maintaining head in desired position requires large recruitment of muscles
* Esp if spine is subject to supramaximal constraints during an intense physical effort
-Player on verge of consciousness can no longer recruit muscles to the extent that is required for protection of their spine (cannot rigidify spine)
* More likelihood of injury
123
Helicopter pilots are required to isometrically sustain a 70% load for up to 3 minutes in order to return to flying (while wearing gear). True or false
TRUE
124
In super rugby competition, forwards spend an average of 7.1 +/- 2.7s in static play (rucking, mauling, scrumming). True or false
True
- assess neck in function capacity that sport requires
Simulated dynamic loading that occurs in rugby game
* Endurance protocol requiring participants to sustain 70% maximal contraction for at least 7s interspersed with 4s at 90% maximal contraction
125
what diagnostic and RTP test/improve neck function can be done?
- Reposition target laser
- Neck repositioning is something athletes struggle with after both neck and head injuries
126
Explain the mechanisms and types of fractures.
Our role to assess the biomechanics of the fracture
- 1/3 occurs at C2
* Major changes in biomechanical load, flexion and extension
- 1/3 occurs at C6/7
- Benign vs unstable
Lx more vertebrae, less facet
Cx more facet, less vertebrae
127
Explain the Denis Spinal Columns.
3 column concept in spinal fracture.
If injury is only in 1 column, not that serious.
2 or more columns = loss of stability
ANT column
- ant longit lig
- ant annulus
- ant 2/3 vert body
MID column
- post 1/3 vert body
- post annulus
- post longit lig
POST column
- post elements: pedicles, facts, lamina, spinous process
- pos lig
128
What are the mechanisms of injury in excessive/full FLEX in spine?
- Disruption of spinous processes
- Ligamentum nuchae (positioned along the spinous processes) will be pulling and may snap off the spinous process
- Considered a benign fracture
129
What is the Clay-Shoveler fracture?
-Avulsion fracture of spinous process of c6/c7 (also towards t1)
-Abrupt flexion of neck with contraction of lower neck muscles
-Can be stress fracture or direct trauma
-Ligamentum nuchae, traps, rhomboids all pulling at this area
-Benign condition, should resolve with attention to what caused the injury in the first place
130
What is a compression fracture (burst fracture)?
Axial loading could cause burst fracture in anterior column
* Benign, doesn’t involve spinal cord or other structures – not catastrophic
* Intact posterior body to prevent injury to SC
131
What happens in hyperflexion if interspinous lig's are disrupted?
*Subluxation but not dislocation
*Ligamentous instability
*Loss of ability of CS to maintain relationships between vertebrae under physiological loads in a way that will prevent damage to SC or nerve roots/cause irritation, deformity and pain
132
what is a simple wedge in spine hyperflexion mean?
* Still stable
* VB fracture but interspinous ligament intact
133
What does an unstable wedge mean when in hyperflexion of spine?
*Fracture + tearing of interspinous ligament
What happens when they go into flexion/extension? Is there segmental fluidity/asymmetrical spacing between spinous processes?
- Need to catch so they don’t lose normal lordosis and cause more problems later on
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What happens in spine hyperflexion+rotation?
- Bilateral dislocation
- Facet joints slipping
Compression to SC as continuity of VC is disrupted
* Risk of cord damage
* Long recovery period
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What happens in spine hyperflexion extreme with axial load?
- Risk of cord damage
- Very high Newtons of force
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What happens to spine in extreme extension?
- Hangman’s fracture --> Traumatic unstable fracture
- Unlikely to get cord irritation/damage so looking for signs of paralysis and arm/leg movement will not be indicative/may be misleading
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What happens when spine is extended + rotation?
extension teardrop!
- unstable + cord injury risk
- high N of force (MTV etc)
Swelling of cord + hemorrhaging within cord
^ requires surgical stabilization and decompression
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what is the low-Risk Criteria for Clinical Exclusion of Cervical Spine Injury in Alert Stable Patients
Clearance = confident exclusion of unstable cervical spine injuries that could otherwise result in neurologic injury/death
- Nexus criteria - 99.8% predictive values (only missed 8/818 cases)
- Canadian C-Spine rule criteria
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What is the Nexus Criteria?
- No posterior midline cervical tenderness
* Palpation down back of neck
- No intoxication
* Patient won’t be in control of higher cerebral functions, can’t give us accurate answers
-No focal neurologic deficit
-No painful distracting injuries
* Eg. another injury that is more obvious like a broken leg
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What is the Canadian C-Spine rule criteria
- Age <65y
- No dangerous mechanism such as
* Fall from height >91cm (3x their height more accurate since everyone is different heights?)
* Axial loading injury (like a diving accident)
* High-speed motor vehicle collision
* >100km/h, rollover or ejection from vehicle
* Recreational motor vehicle
* Motorcycle or bicycle injury
- No paresthesia
- Sitting position in emergency department
* If they are sitting comfortably, it is unlikely that they have a catastrophic neck fracture
- Ambulatory at any time
* Movement
- Neck rotation of 45 degrees left and right
* Active ROM Don’t do it for them
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What does a GCS <8 mean?
intubate and ventilate!
Should be getting GCS of 15 (may lose 1 here and there)
Inanimate objects can get GCS of 3
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What is the anatomy of a spinal cord?
- POS columns
- ANT horn
- Corticospinal tract
- spinothalamic tract
- spinocerebellular tract
layers of fibres combine together and ascend up spinal cord - eventually communicate with brain
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What is central cord syndrome?
-Likely that legs aren’t affected but upper limbs are
-Incomplete injury
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What is ANT cord syndrome?
- more likely to take out more of psinal cord
could explain different presentations people have
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List some characteristics about C2 fractures.
account for nearly 19% of all spinal fractures and 55% of Cx fractures
-Sudden forceful hyperextension centered just under the chin
-Expands the spinal canal
-Hangman fracture
*Usually unstable, need halo device but some patients can and have walked themselves off the field
* Neurologically intact doesn’t mean no injury to spinal cord and nerves at level of fracture
* May not have any focal or neurological signs such as symptoms in their arms and legs
* Presents itself as neck pain or neck spasms
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What happens in transient quadriparesis/paralysis?
Eg. Can’t feel legs but then is suddenly fine
* Not a miracle, sign of a problem
-Players who experience this may have a rapid and complete resolution
BUT should be strongly advised to have xray/MRI
-Should never be allowed to return to field if symptoms persist
-Record this event down
* Could be an event of compromise (below) and next injury may not heal as well
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What is Cx spinal stenosis?
-Degenerative change within spinal canal which causes compromise
* Hyperextension movements can pinch spinal cord, causing spinal swelling
-Spinal cord has undergone concussion
-Can present itself in the limbs
-Possible to have neurological but not muscular signs
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What is the difference between acquired vs congenital Cx spinal stenosis?
Acquired stenosis:
*Becomes arthritic and compromised
Congenital stenosis:
*The way the body has developed naturally
*Spinal canal too small to suit certain sports/for person to take the risk and play contact sports
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What are the symptoms of nerve root traction or compression injury (stinger/Burner)?
- Episodic shooting/electrical pain with acute onset after an impact to head/shoulder
- Burning pain or dead arm (may be dealt with as dislocation)
- Numbness or tingling
- Unilateral upper extremity
- Neck bending causes symptoms and prolonged burning pain, neck pain
- weakness of shoulder elevation, elbow flexion, grasping
- Any suggestion of weakness from c4-t1 is indicative of injury to cervical roots of brachial plexus
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Explain the process of nerve root traction/compression injury in RTP?
- Minimal time loss of 0-1 days (80%)
- Recheck muscle weakness and ask about persisting pain as it can >1 month
- no stretching
- Injury with >3 symptoms especially motor weakness = poor outcomes
- 3rd stinger in same season, player should sit out remainder of game
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What are stingers accompanied with?
Cx abnormalities
e.g. long neck
- compressive injury (concern with stretching if experiencing pain + weakness / compression of nerve roots
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There is a mixture of contributions to areas, hard to test isolated nerves, can use dermatomes. true or false
true
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What is the doorbell sign?
consider location of brachial plexus
-Positive local pain local tissue damage (that is not present on the other side)
-Positive arm pain nerve root irritation or inflammation
* Pain is not present on other side
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What should we do with players who walk off the field with a neck injury?
- should be questioned away from distractions nad coaches
we want honest answers
Seated position
* Test active neck ROM in different planes (don’t move their neck for them as it may aggravate an injury, their body won’t let them achieve ROM that harms them)
- Lateral flexion, flexion, extension, rotation
- Look at ceiling, palpate along midline
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What is the process after a neck injury event?
Displacement does not explain additional traumatic injury, but rather amount of force applied across an unstable segment is key determinant of neurologic deterioration
-Balance between doing no harm and doing right thing
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How to achieve true immobilisation?
current neck collars may not be sufficient
rigid collars > soft collars
require both Cx and Tx immobility
putting collar on = could make injury worse
assess available equipment on field at time
let paramedics do job
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what considerations need to be made for Cx spine in children?
- Fulcrum is different in children vs adults
- Young children typically sustain injury at C1-4 vs older children lower cervical C5-7 (fulcrum change + neck vs head size)
- more elastic/flexible spinal column
- poor musculature (80% muscle, 20% bony)
- open ossification sites
- horizontal vertebral facet joints
- physiologica wedging of vertebral bodies (compression and change due to growth)
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What considerations are made when children experience similar loading ot adults?
they will sustain different injuries.
- should be immobilised during initial evaluation and management if suspected of spinal injury
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What are high risk mehanisms?
-High force or velocity
- Falls from heights >1.5m/3x body length
- Motor vehicle accidents
- Diving injuries
- Blunt traumatic injuries from contact/collision sports
- Any significant acceleration-deceleration injury
^ you may not be able to attain good injury history from a kid
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hat are the triad of symptoms associated with CS injury?
- localised Cx spine pain
- muscle spasms
- limited neck ROM
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What is Spinal Cord Injury Without Radiologic Abnormality (SCIWORA)?
- Should be suspected in patients <8y who have experienced blunt trauma and report immediate transient and neurologic symptoms
- X-rays, CTs normal
- Onset of symptoms may be delayed up to 4 days
- Should run MRI
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What considerations are made on SCIWORA?
*61% patients with clinical diagnosis of SCIWORA have abnormalities on MRI, MRI should be performed when clinical concern for SCIWORA is present
BUT
*Can be a traumatic experience
*Hard to get them to lie still for long time may require sedation? Can we sedate children when there is no actual evidence of SCI?
*Need to make good clinical judgement
