Spinal Cord Compression Flashcards
Why is prompt Dx of spinal cord compression essential?
Rapidly evolving spinal cord compression (hours to days) is a NEUROSURGICAL EMERGENCY which should be managed as soon as possible to avoid permanent neurological disability
Recognise the appearance of extradural, intradural/extramedullary and intramedullary lesions which may compress the spinal cord and cauda equina. Which is the most common?
What are the 5 most common categories of causes of spinal cord compression?
Tumour (primary or metastatic)
Degenerative
Infection
Haematoma
Developmental
List 3 degenerative causes of spinal cord compression
Disc prolapse
OP
Spondylosis
What anatomical features are possible sites of infection which may cause spinal cord compression?
Vertebral body
Disc space
Extradural
Intradural
Give 3 causes of spinal haematoma which may result in spinal cord compression
Spontaneous
Trauma
AVM
List 3 developmental abnormalities which may result in spinal cord compression
Syrinx
AVM
Arachnoid cyst
What is a syrinx?
Syringomyelia is the formation of a fluid-filled cyst (syrinx) within the spinal cord
As the cyst grows, it may compress the spinal cord
Causes include trauma, infection and congenital brain defects
What is an arachnoid cyst?
Cerebrospinal fluid-filled sacs covered by arachnoid cells and collagen that are located between the brain or spinal cord and the arachnoid membrane
Primary arachnoid cysts are present at birth and are the result of developmental abnormalities; secondary arachnoid cysts are not as common as primary cysts and develop as a result of head injury, meningitis, or tumors, or as a complication of brain surgery
Majority form in the middle cranial fossa (spinal cord cysts are less common)
Give 3 examples of extradural causes of spinal cord and cauda equina compression
Metastatic tumour
Abscess
Degenerative spinal disease
Give 3 examples of intradural/extramedullary causes of spinal cord and cauda equina compression
Meningioma
Schwannoma
Myxopapillary ependymoma
Give 2 examples of intramedullary causes of spinal cord and cauda equina compression
Glioma (astrocytoma or ependymoma)
Syrinx
Overview of meningioma (what is it, presentation, Dx, Ix, Mx)
Predominantly benign tumour of the meninges occurring at both cranial and spinal sites; they are occasionally atypical or malignant in nature
Sx: produces symptoms from local mass effect due to compression of neural structures or may present with seizure
Dx: diagnosis confirmed by the characteristic appearance on MRI with and without contrast enhancement
Ix: asymptomatic lesions may be followed up with serial observation
Mx: treatment of symptomatic meningioma is usually surgical resection, although, in some cases, local radiotherapy is used as primary treatment
What is schwanomma?
A schwannoma is a benign nerve sheath tumour composed of Schwann cells, which normally produce the insulating myelin sheath covering peripheral nerves
Less than 1% become malignant, degenerating into a form of cancer known as neurofibrosarcoma
What is myxopapillary ependymoma?
Thought to arise from the ependymal glia of the filum terminale or conus medullaris (at the end of the spinal cord); histologically, they contain papillary elements in a myxoid background, admixed with ependymoma-like cells
What is an ependymoma?
Ependymomas arise from ependymal cells lining the central canal or cell rests along the filum; they are the most common spinal cord tumour overall
What is an astrocytoma?
Astrocytomas (both intracranial and spinal) arise from astrocytic glial cells; spinal cord astrocytomas generally have a lower histologic grade than astrocytomas in the brain
They are the second most common spinal cord tumour overall
If a patient presents with LL neurological disturbance but UL is normal, what does this suggest about the location and level of the lesion?
No cervical spine involvement
What is the most common cause of cauda equina syndrome?
Acute disc prolapse
How might spinal cord compression present differently to cauda equina?
Spinal cord compression can present with UMN signs
In cauda equina syndrome, all signs are consistent with a LMN lesion
What are the two major presenting features of spinal cord compression and cauda equina syndrome? What factors can affect the presentation?
Presentation: pain and neurological deficit
Modified depending on: site of compression, speed of onset, involvement of adjacent nerve roots, cause, and involvement of blood supply of the spinal cord
Mr Verdi, 73, visited his GP complaining of difficulty walking
He could not describe the symptom very well, but thought his legs had been generally weak and stiff; he also noted some trouble with fine movements of his hands
What are these symptoms suggestive of?
Weak and stiff: may suggest UMN lesion
Involvement of hands: suggests cervical spine
Mr Verdi, 73, presents with difficulty walking
Previously well, PHx: OA of knees, occasional low back pain, more recently some neck pain, no surgery, no cancers
Symptoms have been progressively worsening over many months or maybe even years
Walking has been “shuffling” and he feels unable to continue for long distances; he has had a number of falls and feels unsteady
His hands feel numb and he has had trouble with buttoning his shirt and turning the pages of the newspaper
His bladder and bowel function have been normal
O/E: moderate restriction of neck movements due to mild pain and stiffness, shuffling stiff gait, UL power relatively normal but depressed reflexes, light touch sensation in hands diffusely reduced with no clear dermatomal distribution, LL power only mildly reduced but tone elevated and very brisk reflexes, Babinski’s sign positive, light touch sensation in LLs normal but proprioception and vibration reduced
What picture is this?
What anatomical level is the lesion
DDx?
What should Mr Verdi’s GP do next? Ix and Mx?
Mixed picture: UL has LMN pattern, LL has UMN pattern with spastic paraparesis
Hx and Ex suggest a slowly progressive compressive lesion of the cervical spinal cord (a classic “cervical myelopathy”)
In an older patient with neck pain, slow Sx onset, no fever and no Hx of cancer, this is most likely due to degenerative cervical canal stenosis
Main DDx: spinal tumour (primary or metastatic), spinal infection, inflammatory or neurodegeneraive diseases (MS, MND, syringomyelia/syrinx, subacute combined degeneration of the spinal cord)
Ix: baseline bloods, CT scan of cervical spine
Mx: neurosurg referral (who will most likely order an MRI of the cervical spine)
Mr Verdi, 73, presents with difficulty walking and has signs O/E of spinal cord compression
MRI: severe cervical canal stenosis with cord signal change due to disc prolapse, spondylosis and hypertrophy of the ligamentum flavum
Is this an emergency?
No; has a slow progression
Where does degenerative spinal canal stenosis usually occur? What sites produce the most clinically significant presentations?
May occur anywhere along the spinal column
Most clinically significant lesions are in the cervical spine (causing cervical myelopathy due to cord compression) and in the lumbar spine (causing sciatica and neurogenic claudication due to cauda equina compression)
What degenerative changes can contribute to spinal canal stenosis? What factors can contribute to these degenerative changes?
Spondylosis with hypertrophy and osteophytes of the fact joints
Hypertrophy of ligamentum flavum
Bulging or prolapsed intervertebral discs and associated osteophytes
Contributing factors: excessive mobility, often on a background of a congenitally narrow canal
What is the most common cause of spinal cord compression due to degenerative spinal canal stenosis?
Spondylotic spinal myelopathy
What is the effect of surgical intervention on symptoms of a chronically evolving spinal cord compression?
Operation stops the progression of symptoms but does not reverse or improve current symptoms
What is the cause of the neurological symptoms seen in degenerative spinal cord stenosis?
Direct pressure on neural structures
Ischaemia of the neural structures
What pathological changes occur in the spinal cord due to compression and ischaemia of the neural structures?
Degeneration and loss of nerve cells
Spinal cord cavitation
Glial cell proliferation
Demyelination
Wallerian degeneration of tracts above and below the level of compression
Principles of Mx of degenerative canal stenosis
Conservative Mx indicated for: mild, non-progressive disease, the very elderly (although common to treat patients into their 80s), or those unfit for Sx due to comorbidities
Sx treatment indicated for moderate, severe or progressive disease to halt further disability (presenting neurological deficits may be irreversible)
What is the risk with conservative Mx of degenerative canal stenosis?
Risk of sudden, irreversible worsening with even minor trauma
What type of Sx may be indicated for degenerative spinal canal stenosis?
Surgical removal of the compression lesion(s): may involve a posterior or anterior approach
Spinal fusion may be necessary for pre-existing instability or extensive destructive surgery
Name spinal surgeries and specify whether they utilise a posterior or anterior approach
Laminectomy
Discectomy
Vertebrectomy
How is the type of surgery and the approach planned when operating on a degenerative spinal cord stenosis?
Dependent on:
Severity of compression
Number of vertebral levels involved
Whether compression is largely anterior or posterior
Mr Verdi underwent an anterior cervical discectomy and fusion to remove the disc prolapse and fuse the spine at C3/C4, the level of most significant compression and where there was mild instability with movement
He may require a laminectomy from a posterior approach in the future to decompress the rest of the cervical canal
What does the arrow in his post-op XR show?
Plate and anchoring screws across the disc space which contains a “cage” for fusion
Mr Singh, 39, presents with pain and a neurological deficit; he has progressively worsening back and leg pain and recently has noticed difficulty initiating urination
Presents at ED in severe distress, having been unable to pass urine for 8/24
What is the most common cause of this type of presentation? What is its pathophysiology? Why is the PNS affected but not the SNS?
Mx priorities?
What are some “red flags” for back pain?
Most common cause: acute disc prolapse, due to compression of the PNS inside the spinal canal (causes retention due to prevention of ureteric sphincter relaxation)
SNS is outside the spinal cord
Mx priorities: urinary catheter!
Red flags: progressively worsening, not related to position or movement, worse at night/waking from sleep, radiation down back of legs, Hx of fever/cancer/LOW/DM/drug use
Mr Singh, 39, presents with pain and a neurological deficit
Has had back pain for over a year but never before that
Pain is progressively worsening, diffuse low back pain with a deep, boring quality, and is not related to position or movement but is worse at night
There is radiation of the pain down the back of the legs
No Hx of trauma, fever, cancer, LOW, DM, drug use
O/E: normal neurological examination apart from previously enlarged bladder
What does Mr Singh need next?
Symptoms of cauda equina compression, requiring urgent r/v by neurosurgery and an MRI scan of the thoraco-lumbar spine, as well as some routine bloods to look for signs of infection, inflammation, etc
This is Mr Singh’s thoraco-lumbar MRI
What does it show?
Well-defined intradural, extramedullary lesion that enhances with contrast and is compressing the cauda equina
What % of spinal cord tumours are benign?
90%
DDx for an intradural, extramedullary, well-defined lesion in a young patient
Meningioma (usually young woman)
Schwannoma
Dermoid or epidermoid cyst
Metastasis (rare)
What is the effect of surgery on symptoms in a patient presenting acutely with cauda equina syndrome due to a compressive lesion?
Surgical removal of the lesion should result in a return to normal function
What is the most common early feature of cauda equina syndrome?
Pain (usually before neurological deficit)
What is the mechanism of pain in cauda equina syndrome?
Due to:
Involvement of pain sensitive structures including bone and muscle
Compression of nerve roots and spinal cord
What “pain patterns” can be produced by cauda equina syndrome due to compression of nerve roots and the spinal cord?
Diffuse, dull, burning
Sciatica in LLs
Brachalgia in ULs
“Girdle” pain radiating around chest wall
What is the typical pattern of progressive weakness seen with a cervical or thoracic lesion?
Progressive spastic paraparesis with UMN weakness, little or no wasting, increased tone and reflexes, and a positive Babinski’s reflex; will eventually lead to paraplegia
In a cervical lesion the ULs will be involved and the pattern depends on the level of compression: often LMN/nerve root compression at the level of the compression with wasting and depressed reflexes
What sensory level corresponds to the level of the nipples?
T4
What sensory level corresponds to the level of the xiphisternum?
T7
What sensory level corresponds to the level of the umbilicus?
T10
What pattern of sensory disturbance will be seen in a cervical compression?
Sensory disturbance in the appropriate dermatomal pattern
What are the features of Brown-Sequard syndrome and what is the cause?
Contralateral impairment of pain and temperature
Ipsilateral weakness and impairment of proprioception, vibtration and light touch
Due to a laterally placed mass
What pattern of sensory disturbance is seen in intrinsic lesions of the central spinal cord and syringomyelia?
Cape-like loss of pain and temperature sensation
What pattern of sensory disturbance is seen in lesions of the cauda equina and conus medullaris?
Saddle anaesthesia
What compressive syndromes will cause sphincter disturbance and what symptoms will result?
Occurs with compression in any region, but paricularly with conus medullaris and cauda equina
Sx: difficulty initiating urination (usually 1st symptom), followed by urinary retention or incontinence, and subsequent constipation and faecal incontinence
Mrs Abdullah, 61, was treated for breast cancer 3 years ago with a lumpectomy and subsequent local RT and chemotherapy
Has had regular FU and has no known recurrent local or metastatic disease
Presents to her GP with 1/52 of severe back pain and difficulty getting up from a chair this morning (proximal weakness)
Pain is mid-thoracic and radiates around to her anterior chest; it is severe in all postures
O/E: spastic paraparesis, normal ULs, sensory level at T4, bladder painlessly enlarged
Ix?
CT scan of thoracic spine
Mrs Abdullah, 61, was treated for breast cancer 3 years ago with a lumpectomy and subsequent local RT and chemotherapy
Presents to her GP with 1/52 of severe back pain and difficulty getting up from a chair this morning (proximal weakness)
What does this CT scan of her thoracic spine show?
Destructive lesion at T4; vertebral body is replaced by tumour and collapsed, and there is tumour projecting into the spinal canal with spinal cord compression
6 common causative cancers for a malignant spinal cord compression
Lung
Breast
Prostate
Kidney
Lymphoma
Myeloma
What level of the spinal column is most commonly affected by malignant lesions?
Thoracic
Principles of Mx for malignant spinal cord compression
Urgent Ix and Mx to avoid severe permanent disability
Commence dexamethasone to shrink the tumour in the short term
Prompt decision with regards to treatment modality (palliation/symptom control only, radiotherapy, surgery)
What are the indications for palliation/symptom control as treatment of choice for malignant spinal cord compression?
If death from primary cancer imminent or if deficit has been present for more than a few days and is fixed
What are the indications for radiotherapy as treatment of choice for malignant spinal cord compression?
In radiosensitive tumours and only if neurological deficit is mild and non-progressive, without significant neural compression on imaging
After surgical decompression (because tumour resection is generally incomplete)
What are the indications for surgery as treatment of choice for malignant spinal cord compression?
If destabilisation of spine
How is the type of surgical procedure for malignant spinal cord compression decided?
Number of vertebral levels involved
Whether compression is largely anterior (vertebrectomy) or posterior (laminectomy)
Whether spinal fusion is necessary (pre-existing instability or extensive destructive surgery)
Mr WIlliams, 24, BIBA to ED with a GCS of 10; known IVDU and rapidly revived with naloxone
Immediately on awakening he complains of severe neck pain and is noted to be febrile
What are the red flags here?
Lowered GCS
IVDU
Severe pain
Febrile
Mr Williams, 24, BIBA to ED with GCS of 10; known IVDU and on awakening complains of severe neck pain and is found to be febrile
Neck pain has been progressive over 2-3 days and is severe, radiating into both arms and increasing Mr Williams’ usual narcotic use
Has remained in bed for last few days until his girlfriend called in an ambulance
Has been unwell and feverish
O/E: temperature 39 degrees C, number of infected track marks and rotten teethi, holds cervical spine rigid, bilateral reduction of biceps and triceps reflex and weakness of elbow flexion and extension, increased reflexes in LLs
Ix?
FBE
Blood cultures
MRI of cervical spine
Mr Williams, 24, is BIBA to ED with a GCS of 10; known IVDU and on awakening complains of severe neck pain and is found to be feverish
What does his cervical spine MRI show?
T1-weighted sagittal MRI with contrast (left) shows C5/C6 discitis wtih an associated epidural abscess from C5 to C7 that enhances with contrast
T2-weighted sagittal MRI (right) showing cord compression due to the abscess
What is the common spinal region for a spinal abscess?
Thoraco-lumbar region
Describe the possible pathophysiologies of spinal abscess
Haematogenous spread to disc or epidural space from distant infected site (skin, respiratory tract, sinuses, middle ear, teeth, genitourinary tract, endocarditis, infected prosthesis, phlebitis, IVDU, infected wound)
Direct spread from adjcent infection, including vertebral body, decubitus (pressure) ulcer, paraspinal or psoas abscess
Should empirical Abx be given for a patient with a suspected spinal abscess? Should a LP be performed?
No, because it will mean that sampling during the operation will not be accurate
LP will not show any meaningful results
What is the most common micro-organism causing spinal abscess?
Staph aureus (or other Staphs)
List some common micro-organisms responsible for spinal abscess
Often unknown
Bacterial: staph, strept, Gram negatives, anaerobes, multiple
Mycobacterial: MTB
Fungal: aspergillus, actinomyces, nocardia, cryptococcus
Other: parasites, syphilis (rare)
What is the clinical presentation of spinal abscess and what is the mechanism of these signs/symptoms?
Presents with severe local spinal pain, rapidly progressive neurological deficit, systemic features of infection
Spinal cord compression due to inflammatory swelling and pus (mostly extradural), cord ischaemia due to thrombosis of arteries and veins (may lead to rapid and irreversible neurological deterioration)
Principles of Mx for spinal abscess
Emergency Ix and transfer for neurosurgical assessment
Emergency surgical decompression
Broad spectrum Abx until micro-organism isolated and sensitivities known
What is subacute combined degeneration of spinal cord?
Lichtheim’s disease
Degeneration of the posterior and lateral columns of the spinal cord as a result of vitamin B12 deficiency (most common), vitamin E deficiency and copper deficiency
How does subacute combined degeneration of the spinal cord (Lichtheim’s disease) present?
Gradual and uniform onset
Weakness and parasthesia of ULs, LLs and trunk
Vision changes and change of mental state
Bilateral spastic paresis may develop
Pressure, vibration and touch sense are diminished
