Medical Diseases of the Spinal Cord Flashcards
What is myelopathy?
Pathology of the spinal cord
What is myelitis?
Inflammation of the spinal cord
What is radiculopathy?
Pathology of nerves (radiculo = nerve)
What is radiculitis?
Inflammation of the nerves (not common)
What is myeloradiculopathy?
Pathology of the spinal cord and nerve
How can the causes of myelopathy or radiculopathy be divided?
Intrinsic or extrinsic
Medical or Surgical
What are the medical causes of myelopathy or radiculopathy?
Inflammation Infarction Infiltration Infection Degenerative (neurons)
What are the surgical causes of myelopathy or radiculopathy?
- Tumour: extradural, intradural/ extramedullary, intramedullary
- Vascular abnormalities: haemorrage, AVM, dural fistula
- Degenerative (spine)
- Trauma
What are the signs of a Upper Motor Neuron problem?
Increased tone
- Spasticity
- Clasp knife
Increased reflexes
Pyramidal pattern of weakness
Babinski sign
Pronator drift (associated with spasticity)
What is a pyramidal pattern of weakness?
A pattern of weakness in the extensors of upper limbs and flexors in lower limbs
What are the signs in lower motor neuron lesions?
Nerve damage causes muscle wasting
Decreased tone
Decreased reflexes
Weakness
What is the difference in paralysis of uper motor neuron lesion and lower motor neuron lesion?
Lower motor neuron lesion = flaccid paralysis
-Paralysis accompanied by loss of muscle tone.
This is in contrast to an upper motor neuron lesion, = spastic paralysis -Paralysis accompanied by severe hypertonia.
What are the sensory signs in radiculopathy?
Dermatomal pattern of sensory loss
C5,6
L5,S1
What is Brown-Sequard Syndrome?
Ipsilateral Side
- UMN signs (Corticospinal tract damage)
- Loss of sensory information (vibration, proprioception - Dorsal column)
Contralateral side
-Loss of pain and temperature
(STT)
What are the medical causes of myelopathy?
Demyelination (MS) Ischaemic Transverse myelitis Neurodegenerative Metabolic, B12 deficiency Malignant/ infiltrative Infective Inflammatory
What are the ischaemic causes of myelopathy?
Atheromatous disease Thromboembolic disease Arterial dissection Systemic hypertension Hyperviscosity syndromes Vasculitis Venous occlusion Endovascular procedures Decompression sickness Meningovascular syphilis
What is transverse myelitis?
Transverse myelitis = spinal cord is inflamed across entire width.
Inflammation damages nerve fibers, causes them to lose their myelin coating -> decreased electrical conductivity in the CNS.
Partial transverse myelitis and partial myelitis = inflammation of the spinal cord that affects part of the width of the spinal cord.
What neurodegenerative disorders can cause myelopathy?
Friedrich’s ataxia
Spinocerebellar ataxias
What infections can cause myelopathy?
Lyme disease
AIDS
Explain the posterior and anterior spinal cord in relation to stroke
Anterior 2 thirds of the spinal cord are supplied by a single spinal artery
Posterior 1 third supplied by 2 arteries
Anterior (where all the motor function is) is much more at risk to spinal stroke
What is the clinical presentation of spinal cord stroke?
May have vascular risk factors
Onset may be sudden or over several hours (unlike brain stroke)
Pain
- Back pain/ radicular
- Visceral referred pain
Weakness
Numbness and paraesthesia
Urinary symptoms
Describe weakness in spinal stroke
Usually paraparesis rather than quadraparesis given vulnerability of thoracic cord flow related ischaemia
What urinary symproms may you see in spinal stroke?
Retention followed by bladder and bowel incontinence as spinal shock settles
Give some general points about spinal cord stroke
Very rarely posterior spinal artery -> dorsal column spared
Usually anterior spinal artery
Occlusion of a central sulcal artery can present as a partial Brown-Sequared syndrome
Usually mid thoracic
May be spinal shock
What is spinal shock?
Spinal shock is a loss of sensation accompanied by motor paralysis with initial loss but gradual recovery of reflexes, following a spinal cord injury (SCI) – most often a complete transection.
Reflexes in the spinal cord below the level of injury are depressed (hyporeflexia) or absent (areflexia), while those above the level of the injury remain unaffected.
What is the investigation for spinal cord stroke?
MRI
What is the treatment for spinal cord stroke?
Supportive
Reduced risk of recurrence
- Maintain adequate BP
- Bed rest
- Reverse hypovolaemia/ arrhythmia
Occupational therapy and physiotherapy
Manage vascular risk factors
What is the prognosis for spinal cord stroke?
Return of function depends of degree of parenchymal damage
Unless significant motor recovery in first 24 hours chance of major recovery is low
Pain may be persistent and significantly contribute to disability
20% mortality, only 35-40% have more than minimal recovery
What is demyeliniting myelitis?
Usually part of MS
Common cause of medical spinal cord disease
Can affect the young
What is demyelinating myelitis of MS?
Characterised by pathological lesions of inflammation and demyelination leading to temporary neuronal dysfunction
Affects the white matter of the CNS
One or more lesions anywhere
Describe the presentation of demyelination myelitis of MS
Partial or incomplete transverse myelitis
May be the initial presentation of MS
-60-70% have MRI brains typical of MS
Subacute onset (over days to a week)
May be history of previous neurological or ophthalmic episodes
How do you diagnose Myelitis in MS?
Typical history -> MRI -> diagnosis
If the history and scan are atypical you can go a lumbar puncture
What is the treatment of MS Myelitis?
Supportive
-lots of options for symptoms
Methylprednisolone
- Very high dose steroids
- Helps with current episode
- Will not prevent future relapse
Disease modifying treatments
What are the causes for transverse myelitis?
Idiopathic Viral Other infections Autoimmune Malignancies Post vaccination
What virus’ may cause transverse myelitis?
VZV, HSV, CMV, EBV, influenza, echo virus, HIV, hepA, rubella
What other infections may cause transverse myelitis?
Syphilis
Measles
LYMES DISEASE
What autoimmune disorders may cause transverse myelitis?
SLE
sjogren’s syndrome
sarcoidosis
Describe vitamin B12 deficiency
Abundant in meat, fish and most animal by-products
Legumes
Absorption from gut requires intrinsic factor
Complicates total gastrectomy, Crohn’s, tape worms
What is Pernicious anaemia?
Autoimmune condition in which antibodies to intrinsic factor prevent B12 absorption
Where does B12 deficiency effect in the nervous system
Most of it:
- Myelopathy (L’hermitte’s)
- Peripheral neuropathy
- Brain
- Eye/optic nerves
- Brainstem
- Cerebellum
What are the signs of B12 deficiency?
Parasthesia hands and feet, areflexia
First UMN sign is upturned plantars
Degeneration of:
- CST -> paraplegia
- Dorsal column -> sensory ataxia
Painless retention of urine
In a patient with absent ankle jerk and upgoing plantars what should you suspect?
B12 dieficiency should be investigated
