Transcript Spinal Cord Syndromes Resident Rounds April 12, 2007 Juliette Sacks

Spinal Cord Syndromes
Resident Rounds
April 12, 2007
Juliette Sacks
Anatomy
• Spinal cord ends as
conus medullaris at
level of first lumbar
vertebra
• lumbar and sacral
nerve roots exit below
this and form the
cauda equina
Neuroanatomy
• Corticospinal tracts
• Spinothalamic tracts
• Dorsal (posterior) columns
Corticospinal Tract
• Descending motor pathway
• Forms the pyramid of the medulla
• In the lower medulla, 90% of fibers decussate
and descend as the lateral corticospinal tract
• Synapse on LMN in the spinal cord
• 10% that do not cross descend as the ventral
corticospinal tract
• Damage to this part cause ipsilateral UMN
findings
Spinothalmic Tract
• Ascending sensory tract from skin and
muscle via dorsal root ganglia to cerebral
cortex
• Temperature and pain sensation
• Damage to this part of the spinal cord causes:
– Loss of pain and temperature sensation in the
contralateral side
– Loss begins 1-2 segments below the level of the
lesion
Dorsal (Posterior) Columns
• Ascending neurons that do not synapse until
they reach the medulla at which point they
cross the midline to the thalamus
• Transmits vibration and proprioceptive
information
• Damage will cause ipsilateral loss of vibration
and position sense at the level of the lesion
Complete vs Incomplete
• Incomplete:
– Sensory, motor or both functions are partially
present below the neurologic level of injury
– Some degree of recovery
• Complete:
– Absence of sensory and motor function below the
level of injury
– Loss of function to lowest sacral segment
– Minimal chance of functional motor recovery
Light touch…
• Transmitted through both the dorsal
columns and the spinothalamic tracts
• Lost entirely ONLY if both tracts are
damaged
Case #1
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33 yo F fell off a 20’ cliff snowboarding
C/o inability to move both legs
GCS 15 BP 130/68 HR 89 regular
Normal UE exam
No power in LE
Vibration and position sense normal in LE
Sensation normal in LE
No rectal tone or perianal sensation
Anterior Cord Syndrome
• Damage to the corticospinal and
spinothalamic tracts
• Dorsal column function is intact
• Loss of:
– Motor function
– Pain and temperature sensation
• Vibration, position and crude touch are
maintained
ACS cont’d
• Causes:
– Direct injury to anterior spinal cord
– Flexion injury of cervical spine causing a
cord contusion
– Bony injury causing secondary cord injury
– Thrombosis of anterior spinal artery
Symptoms
• Complete paralysis below the level of
the lesion with loss of pain and
temperature sensation
• Preservation of proprioception and
vibration sense
What to do?
• Urgent CT/MRI
• Surgical decompression may be an
option
• Prognosis: POOR
Case #2
• 24 y.o. M came off motorcycle at high speed
• Wore no helmet and sustained severe head
injury
• C-spine films were unremarkable apart from a
narrow spinal canal
• Once conscious, he was quadriparetic with
2/5 power in most muscle groups
• No other neurological findings
Where is the lesion?
What’s the deal?
• MRI:
– Mild swelling of the cord at C3/4
– Prevertebral soft tissue swelling and
disruption of anterior longitudinal ligament
• Prognosis:
– Within 48h, power in UE 3/5 and LE 4/5
– At 2/12, further but not full recovery
Central Cord Syndrome
• Older patients
• Preexisting central
spondylosis
• Hyperextension injury
• Injury affects central cord>
peripheral cord
• Damage to corticospinal
and spinothalamic tracts
• Upper extremities>thoracic
>lower extremities>sacral
CCS
• Present with:
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Decreased strength
Decreased pain and temperature sensation
Upper>lower extremities
Spastic paraparesis/quadriparesis
Maintain bladder and bowel control
• Prognosis: GOOD
– Although fine motor recovery of the upper
extremities is rare
Case #3
• 24 y.o. M stabbed in the
neck during stampede
argument over whose
doolie tires were bigger
• No LOC
• C/o inability to pick up his hat with his left
hand
• Unaware of his girl holding his right arm
Brown-Séquard Syndrome
• Hemisection of the cord
• Ipsilateral loss of:
– Motor function
– Proprioception and vibration sense
• Contralateral loss of:
– Pain and temperature sensation
BSS
• Caused by:
– Penetrating injury
– Lateral cord compression from:
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Disk protrusion
Hematomas
Bone injury
Tumours
• Prognosis: GOOD
Case #4
• 76 y.o. Grandpa says he’s got “the
rheumatism some bad in his legs” with the
crazy weather these days
• His wife tells you “he’s wetting himself” which
is unlike him
• He seems to be having lots of trouble riding
his bike because he thinks the bike seat isn’t
under him when it actually is
Cauda Equina Syndrome
• Peripheral nerve injury to lumbar, sacral and
coccygeal nerve roots
• Symptoms:
– Variable motor and sensory loss in lower
extremities
– Sciatica
– Bowel and bladder dysfunction
– Saddle anaesthesia
• Prognosis: GOOD
ED Stabilization
• ABCs
• Airway:
– Low threshold for definitive airway in
patient with cervical spine injury especially
if higher then C5
– Spinal immobilization very important
Spinal Shock
• Loss of neurological function and
autonomic tone below level of lesion
• Loss of all reflexes
• Resolves over 24-48h but may last for
days
• Bulbocavernosus reflex returns first
Spinal Shock
• Symptoms:
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Flaccid paralysis
Loss of sensation
Loss of DTRs
Bladder incontinence
Bradycardia
Hypotension
Hypothermia
Intestinal ileus
Hypotension
• Must determine cause:
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Spinal cord injury
Blood loss
Cardiac injury
Combination of above
• Blood loss is the cause of hypotension until
proven otherwise!
• Vitals are often non specific
• R/O other causes with: CXR, FAST, CT
Neurogenic Shock
• Neurogenic Shock:
– Warm
– Peripherally vasodilated
– Bradycardic
• Bradycardia may be caused by something
other than neurogenic shock
• Cervical spine injury may cause sympathetic
denervation
• Resuscitate with fluids +/- vasopressors
Corticosteroids
• Controversial
• Based on NASCIS trials
• Methylprednisolone improved both
motor and sensory functional outcomes
in complete and incomplete injuries
• Benefit dependent on dose and timing
of dose
Corticosteroids
•
NASCIS recommends:
1. Treatment must begin within 8h of injury
2. Methylprednisolone 30mg/kg bolus iv over 15
minutes
3. 45 minute pause post bolus
4. Maintenance infusion 5.4mg/kg/h
methylprednisolone is continued x 23h
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Evaluated in blunt injury only
Large doses of steroids in penetrating injury
may be detrimental to recovery of
neurological function
Steroid Therapy as per NACSIS
• Attributed to antioxidant effects
• Treat for 24h in patients treated within
3h of injury
• Treat for 48h in patients treated within
3-8h of injury
• Worse outcome if started 8h post injury
• Conflicting evidence re benefit therefore
more trials required
Pros
• Believed to inhibit
formation of free
radical-induced
peroxidation
• May increase spinal
cord blood flow
• Increase extracellular
calcium
• Prevent potassium loss
from cord
Cons
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Pneumonia
Sepsis
Wound infection
GIB
Delayed healing
NASCIS I
Bracken et al. 1984. Efficacy of
methyprednisolone in acute spinal cord injury,
JAMA, 251:45-52
• Prospective, randomized double blind trial
with 330 patients
• 2 treatment arms:
– 100 mg bolus MP, then 25 mg q6h x 10 d
– 1000 mg bolus, then 250 mg q6h x 10 d
• No sig difference in primary outcomes
• 4x increase in wound infections in high dose
group
• “Trend” towards increased sepsis, PE, death
in higher dose group
NASCIS II
Bracken NEJM 1990; 322: 1405-11
• DBRCT of methylprednisone vs naloxone
vs placebo (total N=487)
• Methylprednisone 30 mg/kg bolus then 5.4
mg/kg/hr X 23 hours
• Outcome = neurological function at 6
weeks and 6 months assess by a neuro
function score
• NO benefit of naloxone
• NO benefit of steroids overall
• NO difference in mortality
• Trend to more infections and GI bleeds
with steroids
NASCIS II
• Post – hoc SUBGROUP ANALYSIS
showed a benefit at 6 months in the
subgroup treated within 8 hrs
– Improved motor score: 4 points (p < 0.03)
– Improved Touch score: 5 points (p < 0.03)
– Improved pin-prick score: 5 points (p < 0.02)
• Concluded that steroids were indicated if
started within 8hrs
• One year data showed similar
improvement in motor score but no
difference in sensory scores (Bracken. J Neurosurg
1992; 76; 23-31)
NASCIS III
Bracken JAMA 1997: 277(20); 1597-1604
• DBRCT of methylprednisone 24hrs vs 48
hrs vs Tirilazad (total N=499)
• NO placebo arm
• Overall, NO difference between the
three groups
• Post-hoc subgroup analysis: 48 hour
steroid group showed improved motor
scores at 6 weeks and 6 months if started
between 3-8hrs
– 6 weeks: 5 points motor score (p <0.04)
– 6 months: 4.4 points (p <0.01)
NASCIS III
• Adverse outcomes
– Severe pneumonia higher in 48hr group
• 2.6% vs 5.8% (p<0.02)
– Severe sepsis higher in 48hr group
• 0.6% vs 2.6% (p< 0.07)
• They concluded
– Steroids indicated for SCI
– If started within 3hrs, treat for 24hrs
– If started within 3-8hrs, treat for 48hrs
Cochrane Review
• “the randomized trials of MPSS in the
treatment of acute SCI provide evidence for a
significant improvement in motor function
recovery after treatment with the high dose
regimen within 8 hours of injury”
• Bracken November 2000
• Update in Spine 2001 by Bracken
• 4 trials and 797 patients randomized to get high
dose methylpred vs placebo for 24 hours
Cochrane Review Results
• Primary outcome = neurological
improvement at 6 weeks, 6 months, 1
year
• Complicated motor and sensory exam
• High dose methylpred associated with
4/70 point increase in motor function
at 6 weeks, 6 months but not one
year
SCI and Steroids
• Clinical relevance?
– 4 points spread over 14 muscle segments unilaterally
– Not validated score
– No inter-rater reliability
• Conclusions based on post-hoc analysis of small
subgroup from 1 trial
– 65 patients per arm
– Data drudging
– High risk of alpha error
• Serious complications (not statistically significant)
– GI bleed and wound infection (RR 4.00, 95% CI 0.4535.58)
– Severe pneumonia (RR 2.25, 95% CI 0.71-7.15)
– Range of values in CI huge  do the risks outweigh the
benefits??
SCI and Steroids
• Author consultant for Pharmacia (they
make methylprednisolone)
• Weak support for use of high dose
methylpred in acute SCI + may be
increased risk of severe adverse
outcomes.
Bottom Line
• CAEP position statement : steroids are NOT
STANDARD OF CARE
• There is insufficient evidence to support the use
of high dose methyprednisolone within 8 h of
acute SCI
• Significant harm to using steroids
• NASCIS subgroup data needs to be validated in
prospective, randomized, blinded trials
• No new literature to argue for or against this
Neurological Examination
• LOC
• Deteriorating course
• Neck, back pain and/or bladder, bowel
incontinence should increase suspicion of sc
injury
• Define level of lesion
• Motor function
• Sensory level
• Proprioception testing
• DTRs
• Anogenital reflexes
DI
• C-spine films as per c-spine rules/nexus
• CT
• MRI: better for visualizing neurological,
muscular and soft tissue
– If CT negative and patient has positive
neurological findings, this is next step
– Important to image entire spine as 10%
have 2nd injury
Treatment
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Prevent secondary injury
Alleviate cord compression
Establish spinal stability
Assess the neurological deficit and spinal
stability
• Imaging
• Consult spine/neurosurgery
Other cord lesions…
• Malignancy
• Epidural hematoma
• Abscesses
At the end of my rope…
• Urgent care necessary
• MRI is better than CT for imaging spinal cord
• Comprehensive serial neurological exams
important re management options
• Steroids are not the standard of care in
Canada
• Consider spinal shock, neurogenic shock and
other causes of shock in someone with a
spinal cord injury