Transcript Spinal Cord Compression

Spinal Cord Compression
Neurology Academic ½-day
(Emergency Lecture Series)
Chenjie Xia (PGY-3)
Wednesday, July 22, 2009
Test your knowledge
• The ER staff calls you for: “a 58 yo man, known
prostate cancer, presenting with back pain x 2
months and leg weakness x 1 week” The proper
response should be:
– A) “I will come see the patient immediately”
– B) “I’ll come see the patient as soon as I finish
rounding on the floor.”
– C) “I haven’t had lunch yet…I’ll come in the
afternoon.”
– D) “Just leave me his Medicare and phone #’s, I’ll
book him an appointment with the Urgent Neurology
Clinic”
Test your knowledge
• The ER staff calls you for: “a 58 yo man, known
prostate cancer, presenting with back pain x 2
months and leg weakness x 1 week” The proper
response should be:
– A) “I will come see the patient immediately”
– B) “I’ll come see the patient as soon as I finish
rounding on the floor.”
– C) “I haven’t had lunch yet…I’ll come in the
afternoon.”
– D) “Just leave me his Medicare and phone #’s, I’ll
book him an appointment with the urgent neurology
clinic”
One of the only true
neurological emergencies…
where time is of the essence (i.e.
drop everything else you’re doing)
Test your knowledge
• Can you name 2 causes of spinal cord
compression and 2 mimickers of spinal
cord compression?
Differential Diagnosis
• Common causes
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Neoplasm
Fracture
Cervical / lumbar stenosis
Herniated disk
Spinal infection/abscess
Spinal hemorrhage
Conus medullaris lipomas
• Mimickers
–
–
–
–
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Anterior spinal artery infarction
Spinal AVMs
Multiple sclerosis / transverse myelitis
Neurosarcoidosis
Plexopathy
Anatomy review
• Spinal cord ends at
L1-L2
• Dural sac ends at S2
• Terminology
– Conus medullaris: most
distal bulbous part
– Filum termiale: tapering
part of conus
medullaris (mostly
fibrous tissue)
– Cauda equina: distal
collection of nerve roots
http://en.wikipedia.org/wiki/Filum_terminale
The real estate of cord
compression…location is key!
• Intradural intramedullary:
– astrocytomas, ependymomas,
hemangioblastomas (primary
spinal tumours)
• Intradural extramedullary:
– Meningiomas
– nerve sheath tumours
(schwannomas and
neurofibromas)
• Epidural: metastases
http://www.emory.edu/ANATOMY/AnatomyManual/back.html
Test your knowledge
• What is the most common mechanism
leading to epidural metastasis?
Pathophysiology - Epidural Mets
1) Hematogenous spread to bone marrow
–
Most common mechanism
–
Most at vertebral mass
2) Direct invasion through intervertebral foramina from
paravertebral source
–
Second most common mechanism
–
Typical of lymphoma
3) Retrograde venous spread
–
With increased abdominal pressure, abdo/pelvis venous
system drains via Batson paravertebral plexus to epidural
venous plexus
–
Common for pelvic tumours (prostate)
Pathophysiology - Cord Damage
•
Severity
– Mild: minor Asx indentation of thecal sac
– Severe: strangulation of cord with paraplegia
•
Progression
– Epidural venous plexus obstructed  BBB breakdown 
vasogenic edema  PGD (hence utility of steroids)
– First WM involved  demyelination
– Then GM involved  cord ischemia / infarction
– Irreversible damage if prolonged compression with cord
infarction (> 1 week)
Test your knowledge
• Which of the following is true?
– A) Patients with cancer have high likelihood of
developing spinal cord compression
– B) Patients with cancer are more likely to
develop vertebral metastases without spinal
cord compression
– C) The most common primary cancers
responsible for cord compression are similar
for adults and children
Test your knowledge
• Which of the following is true?
– A) Patients with cancer have high likelihood of
developing spinal cord compression
– B) Patients with cancer are more likely to
develop vertebral metastases without spinal
cord compression
– C) The most common primary cancers
responsible for cord compression are similar
for adults and children
Epidemiology
•
Most common
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–
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Adults: lung, breast, prostate, lymphoma, sarcoma,
kidney
Children: Ewing’s sarcoma, neuroblastoma, germ
cell neoplasms, Hodgkin’s lymphoma
In cancer patients
–
–
likelihood of epidural spinal cord compression 5-yrs
before death = 2.5%
Vertebral metastases >>> ESCC
That being said…
all patients with new back pain and
known malignancy have spinal cord
compression until proven otherwise
Now that you’ve thought of the Dx,
focus Hx and exam on:
1)
2)
3)
4)
5)
Back pain
Weakness
Reflexes
Sensory loss
Spincter control
Test your knowledge
• Which of the following regarding epidural
spinal cord compression is false?
– A) Pain is a more common initial presentation
than weakness
– B) Initial severity of weakness and ambulation
status are important prognostic factors
– C) The sensory level can be 5 levels below the
actual level of compression
– D) Pain improves with supine position
Test your knowledge
• Which of the following regarding epidural
spinal cord compression is false?
– A) Pain is a more common initial presentation
than weakness
– B) The sensory level can be 5 levels below the
actual level of compression
– C) Initial severity of weakness and ambulation
status are important prognostic factors
– D) Pain improves with supine position
Back Pain
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Initial complaint in 96%
May precede neuro Sx by days or years
(duration related to tumour growth rate);
average 7 weeks
Constant, worse with coughing, sneezing,
straining, exercise
Worse when supine (as opposed to disc
disease)
May be radicular (L’hermitte sign in cervical
lesion, “tight rope / band around chest” in
thoracic lesions)
Percuss / palpate chest to better localize pain
Weakness
•
Present in 80% initially (50% ambulatory; 35%
paraparetic; 15% paraplegic)
Rate of progression depends on tumour
growth rate (30% become paraplegic in 1
week)
Usu. paraplegia = cord infarction (likely
irreversible)
Pattern of weakness depends on site of
compression
•
•
•
–
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e.g. above conus = pyramidal pattern
T6-T10: Beevor sign
Reflexes
• Hyperreflexia, upgoing toes (may not be
seen in cauda equina lesions)
• Abdominal reflexes (helpful if present and
asymmetric)
Sensory loss
•
•
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Present in 78% of patients at diagnosis
“Pins and needles,” “numb”
Look for sensory level
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–
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•
Begin distally, then ascend (use pin, go all the way
up to neck)
Look for Brown-Sequard syndrome
Usu 1-5 levels below actual compression
Pattern as per site of compression
•
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Above cauda equina, if intramedullary  sparing of sacral
dermatomes
At cauda equina  saddle anesthesia
Test your knowledge
• Patients with epidural spinal cord
compression may develop:
– A) Urinary incontinence
– B) Urinary retention
– C) Stool incontinence
– D) B and C only
– E) A, B, and C
Test your knowledge
• Patients with epidural spinal cord
compression may develop:
– A) Urinary incontinence
– B) Urinary retention
– C) Stool incontinence
– D) B and C only
– E) A, B, and C
Spincters
•
Urinary
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Contraction of detrusor muscle
innervated by S2-3-4
Initially flaccid and distended
bladder  retention
Then “decentralized bladder”
becomes active and shrinks,
bladder wall hypertrophies 
incontinence, frequency
Ask about urination, palpate
bladder for fullness, bladder
scan and Foley insertion to
document urine volume
http://www.accessmedicine.com/content.asp
x?aID=707106&searchStr=neurogenic+blad
der
Spincters
•
Rectal tone
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External anal sphincter
and puborectalis muscle
innervated by S3-4
Loss of anal tone 
stool incontinence
Similar mechanism for
bulbocavernosus reflex
DRE, anal wink, tugging
at Foley
http://www.netterimages.com/image/12555.htm
Conus vs Cauda
• Spinal cord ends at
L1-L2
• Dural sac ends at S2
• Terminology
– Conus medullaris: most
distal bulbous part
– Filum termiale: tapering
part of conus
medullaris (mostly
fibrous tissue)
– Cauda equina: distal
collection of nerve roots
http://en.wikipedia.org/wiki/Filum_terminale
Conus vs Cauda
Conus
Cauda
Sudden and bilateral onset
Gradual and unilateral onset
Radicular pain less prominent
Radicular pain more prominent
More low back pain
Less low back pain
Symmetric, distal, hyperreflexic
paresis
Asymmetric, areflexic paraplegia
Symmetric, bilateral, typically
perianal area sensory loss,
sensory dissociation occurs
Asymmetric, unilateral, typically
saddle area, no sensory
dissociation
Early spincter signs
Late spincter signs
Intramedullary vs Extramedullary
• Intradural intramedullary:
– astrocytomas, ependymomas,
hemangioblastomas (primary
spinal tumours)
• Intradural extramedullary:
– Meningiomas
– nerve sheath tumours
(schwannomas and
neurofibromas)
• Epidural: metastases
http://www.emory.edu/ANATOMY/AnatomyManual/back.html
Intramedullary vs Extramedullary
Intramedullary
Extramedullary
Poorly localized burning pain
Prominent radicular pain
“sacral sparing”
Early sacral sensory loss
Corticospinal tract signs
appear later
Early spastic weakness in legs
Usually rapid progression
(usually malignant lesion)
Usually slow progression
(usually benign lesion)
http://www.accessmedicine.com/content.aspx?aID=2904376
Although history and exam are
important, one cannot make a
diagnosis without imaging.
1) Better to err on side of caution, i.e. obtain
imaging even if clinical suspicion low
2) All patients eventually end up having
neuroimaging, i.e. MRI
3) Key point is urgency of timing of
neuroimaging
Test your knowledge
•
If clinical suspicion is high, your next step
should be:
A)
B)
C)
D)
E)
F)
Call your attending
Call the radiologist
Call the radiation oncologist
Call the neurosurgeon
Call the orthopedic surgeon
Call the oncologist
Test your knowledge
•
If clinical suspicion is high, your next step
should be:
A)
B)
C)
D)
E)
F)
Call your attending
Call the radiologist
Call the radiation oncologist
Call the neurosurgeon
Call the orthopedic surgeon
Call the oncologist
Test your knowledge
•
In a patient with suspected compression at
L3 level, you should order an MRI of:
A)
B)
C)
D)
E)
F)
The cervical spine
The thoracic spine
The lumbar spine
The sacral spine
The lumbo-sacral spine
The entire spine
Test your knowledge
•
In a patient with suspected compression at
L3 level, you should order an MRI of:
A)
B)
C)
D)
E)
F)
The cervical spine
The thoracic spine
The lumbar spine
The sacral spine
The lumbo-sacral spine
The entire spine
What to image
• Always image entire spine:
– Spinal cord is shorter than vertebral spinal
column; imaging LS spine means you’re not
imaging the cord at all
– Exam is not always reliable for level of
compression
– Multiple sites of deposits are frequent in
epidural spinal cord metastases (1/3 of
patients)
Test your knowledge
• Which of the following patients may safely
undergo MRI:
– A) A patient with a metal hip prosthesis
– B) A patient with an “MRI-compatible” PPM
– C) A patient with a cochlear implant
– D) A patient with CKD on dialysis
– E) A patient with dental braces
Test your knowledge
• Which of the following patients may safely
undergo MRI:
– A) A patient with a metal hip prosthesis
– B) A patient with an “MRI-compatible” PPM
– C) A patient with a cochlear implant
– D) A patient with CKD on dialysis
– E) A patient with dental braces
MRI contraindications
1) Implanted devices and foreign bodies
– Cardiovascular devices (stents, valves, IVC filters, embolization
coils, loop recorder, pacing devices)
• Most are MR safe/conditional, depends on specific brand
• Timing: If non-ferromagnetic, can scan immediately; If ferromagnetic,
prudent to wait 6 wks for proper tissue anchoring
• Usually recommends < 3Tesla
• Unsafe: Swann-Ganz catheters, temporary epicardial pacing wires,
transvenous temporary pacing leads, PPM/ICDs, IABP, VADs
• Stored information may be affected e.g. loop recorder (download
beforehand)
– Unsafe: nerve stimulators, cochlear implants, ferromagnetic
aneurysm clips, intraocular/intraorbial metal fragments
– Safe: dental alloys / wires / prostheses, most orthopedic implants
– Image artifacts
MRI contraindications
2) Unstable patients
– no MRI, unless urgent clinical indication and no other alternative
3) Pregnancy:
– magnetic field and gadolinium probably safe, but unproven
– Negative effect of noise on fetus?
4) Other
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Claustrophobic and obese patients: open MR machines
Agitated: sedation
Tattoo: usually not a problem
Contrast agents
• Mod-severe CKD: contrast nephropathy (risk <<< iodinated contrast)
• Dialysis, hepatorenal syndrome, periooperative liver transplant:
nephrogenic systemic fibrosis
• Decisions best on a case-by-case basis
• ALWAYS inform radiologist about ANY possible contraindication
Unfit for MRI…
What next?
CT-Myelogram
http://www.beliefnet.com/healthandhealing/im
ages/exh57177_97870_1_lumbar_myelogram
.jpeg
http://www.urmc.rochester.edu/smd/Rad/neurocases/Case34/Fig2.jpg
Diagnosis
• MRI
– Test of choice
• CT myelography
ADVANTAGES
– Non-invasive
– No procedural complication (e.g.
risk of herniation with brain mets,
hemorrhage with coagulopathies,
neuro deterioration with CSF
retrieval)
– Visualization of spinal parenchyma,
adjacent bone and soft tissues
– Can image entire spine even if
subarachnoid block present
– Needed to plan radiation and Sx
– 2nd test of choice
ADVANTAGES
– CSF can be obtained for
analysis
– Safe for claustrophobic
patients
– Safe for ferromagnetic
implant (valves, PM,
implants, shrapnel)
– No movement artifact
Treatment
•
The obvious…
– Abscess: ABX, Sx
– Hematoma: correct coagulopathy, Sx
– Fracture / stenosis: Sx
•
Goals of treatment for epidural
metastases
– Pain control
– Preserve or improve neurological function
Test your knowledge
• Which of the following is false regarding
treatments for ESCC:
– A) There is no significant difference in survival between
high dose and low dose Decadron
– B) There is no significant difference in survival between
short- and protracted-course radiation therapy
– C) There is no significant difference between surgery
followed by radiation therapy and radiation therapy
alone
– D) Anterior approach is superior to posterior approach
in vertebral metastasis removal
Test your knowledge
• Which of the following is false regarding
treatments for ESCC:
– A) There is no significant difference in survival between
high dose and low dose Decadron
– B) There is no significant difference in survival between
short- and protracted-course radiation therapy
– C) There is no significant difference between surgery
followed by radiation therapy and radiation therapy
alone
– D) Anterior approach is superior to posterior approach
in vertebral metastasis removal
Steroids (Decadron)
Initial presentation
Dose recommended
Mild disease, no neurological Sx
Forgo steroids
Moderate disease, minimal
neurological dysfunction, < 80%
spinal block
Low dose: 10mg x1 IV
then 4mg q6h;
then taper rapidly when definitive
Rx underway
Severe disease, significant
neurological dyxfunction
(paraparetic, paraplegic); > 80%
spinal block
High dose: 100mg x1 IV
then 24mg q6h x at least 72 hours
then taper gradually when
definitive Rx underway
Steroids
• Clearly improve neurological outcome
• It seems no difference b/w initial dose of
10mg or 100mg for mild disease
• Adverse effects (gastric ulcers,
hyperglycemia, psychosis, life threatening
infections, etc)
Radiotherapy
• RT portal: centered on spine, 2 vertebral bodies
above and below myelographic block
• No difference in functional outcome or overall
survival b/w different dosing regimens
• Protracted course had better local control of
tumour (less recurrence within field)
• Overall success depends on inherent
radiosensitivity of tumour, neuro status at onset
of RTX, timing of RTX (earlier better)
Surgery
•
Needed for tissue Dx if 1st presentation of
cancer or if spine instability
Adverse effects (wound closure, infection,
spinal instability, nonfusion)
May worsen pain
Older trials (posterior approach):
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Recent trials (anterior approach):
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•
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Sx + RTX = RTX alone
Sx + RTX > RTX alone
Future direction more geared toward Sx?
Careful case-by-case selection
Supportive
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Pain management (steroids usually
relieve pain, opioids help)
Bedrest not helpful (except if has spine
instability)
VTE prophylaxis: heparin sc, TED
stockings, compression
Catheterization, laxatives
Pressure sores
Prognosis
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Most important Px factors: weakness at presentation
Duration of Sx prior to presentation correlate with Px
Sparing of sphincter and sacral sensory = good Px
Px depends on radiosensitivity of tumour
Children overall prognosis better than adults
Median survival 6 months
Recurrence rate 20%
Take Home Messages
• Suspect spinal cord compression in all patients with
cancer and back pain, +/- weakness, sphincter signs
• Goal of history and exam:
– assess severity of neuro deficits (weakness, sensory, sphincter)
– localize lesion (pattern of weakness, sensory level)
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•
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MRI if no contraindication, image whole spine
Involve all relevant consultants
No difference between high and low dose Decadron
Act fast, prognosis directly related to duration and
severity of neuro deficits
• Overall poor prognosis, but pain control and optimize
neuro status crucial for palliation
References
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Medlink: Metastatic epidural spinal cord compression. www.medlink.com. Accessed
2009/07/19
Cole JS and Patchell, RA.. Metastatic epidural spinal cord compression. Lancet Neurol.
2008 May;7(5):459-66
Uptodate: Principles of Magnetic Resonance Imaging (MRI). www.uptodate.com Accessed
2009/07/19
Uptodate: Treatment and prognosis of epidural spinal cord compression, including cauda
equina syndrome. www.uptodate.com Accessed 2009/07/19
Uptodate: Clinical features and diagnosis of epidural spinal cord compressio, including
cauda equina syndrome. www.uptodate.com Accessed 2009/07/19
Medlink:
http/www.uptodateonline.com/online/content/topic.do?topicKey=noninvas/16985&selected
Title=3~150&source=search_result, accessed 2009/07/19
eMedicine Online http://emedicine.medscape.com/article/1148690-overview, accessed
2009/07/19
Raaijmakers, E. et al. Acta Oncologia 2001;40(1):88-91. Always on a Friday? Time pattern of
referral for spinal cord compression.
Harrison’s Online. Access Medicine.
http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4 Diseases of the spinal
cord