Spinal Cord Pathology Flashcards
SCC - Motor Lesions
Amyotrophic lateral sclerosis (motor neuron disease)
Poliomyelitis
SCC - Combined Motor and Sensory Lesions
Brown-Sequard syndrome
Subacute combined degeneration of the spinal cord (vitamin B12 & E deficiency)
Friedrich’s ataxia
Anterior spinal artery occlusion
Syringomyelia
Multiple sclerosis
SCC - Sensory Lesion
Neurosyphilis (tabes dorsalis)
Tracts affected:
1. Dorsal columns
> Loss of proprioception and vibration sensation
Amyotrophic Lateral Sclerosis (MND)
Tracts affected:
- Affects both upper (corticospinal tracts) and lower motor neurone
- Results in a combination of upper and lower motor neuron signs
Poliomyelitis
Tracts affected:
- Affects anterior horns resulting in lower motor neuron signs
Brown-Sequard syndrome (spinal hemisection)
Tracts affected:
- Lateral corticospinal tract
- Dorsal columns
- Lateral spinothalamic tract
Clinical notes:
- Ipsilateral spastic paresis below lesion
- Ipsilateral loss of proprioception and vibration sensation
- Contralateral loss of pain and temperature sensation
Subacute combined degeneration of the spinal cord (vitamin B12 & E deficiency)
Tracts affected:
- Lateral corticospinal tracts
- Dorsal columns
- Spinocerebellar tracts
Clinical notes:
- Bilateral spastic paresis
- Bilateral loss of proprioception and vibration sensation
- Bilateral limb ataxia
Friedrich’s ataxia
Tracts affected: 1. Lateral corticospinal tracts 2. Dorsal columns 3. Spinocerebellar tracts (Same as Subacute combined degeneration of SC)
Clinical notes:
1. Bilateral spastic paresis
2. Bilateral loss of proprioception and vibration sensation
3. Bilateral limb ataxia
(Same as Subacute combined degeneration of SC)
AND
In addition cerebellar ataxia → other features e.g. intention tremor
Anterior Spinal Artery Occlusion
Tracts affected:
- Lateral corticospinal tracts
- Lateral spinothalamic tracts
Clinical notes:
- Bilateral spastic paresis
- Bilateral loss of pain and temperature sensation
NB Sudden onset weakness points towards a vascular cause of neurological impairment
Eg Cocaine can cause vasospasm of anterior spinal artery
Syringomyelia
Tracts affected:
- Ventral horns
- Lateral spinothalamic tract
Clinical notes:
- Flaccid paresis (typically affecting the intrinsic hand muscles)
- Loss of pain and temperature sensation
Multiple Sclerosis
Tracts affected:
Asymmetrical, varying spinal tracts involved
Clinical notes:
Combination of motor, sensory and ataxia symptoms
Syringomyelia
Overview
development of cavity (syrinx) within the spinal cord
if extends into medulla then termed syringobulbia
strongly associated with the Arnold-Chiari malformation
Features
maybe asymmetrical initially
slowly progressives, possibly over years
motor: wasting and weakness of arms
sensory: spinothalamic sensory loss (pain and temperature)
loss of reflexes, bilateral upgoing plantars
also seen: Horner’s syndrome
Spinal Epidural Abscess
Spinal epidural abscess
Key features include
spinal pain
fever
neurological deficit
Example Question:
A 54-year-old man presents with neck pain and feeling generally unwell. This has been getting progressively worse over the past two weeks and is now ‘unbearable’. He feels hot and also complains of headaches.
He emigrated from Pakistan 30 years ago. He smokes 20 cigarattes/day and does not drink alcohol.
On examination pulse is 102/min, blood pressure 124/74 mmHg and temperature 37.9ºC. He has weakness in both arms
MRI of his cervical spine is shown below:
PASSMED SEE EPIDURAL ABSCESS
What is the most likely diagnosis?
Cervical disc prolapse Syringomyelia > Cervical epidural abscess Meningitis Tuberculosis
MRI demonstrates an epidural collection with peripheral contrast enhancement. The cord is displaced posteriorly and to the right. Features are consistent with an epidural abscess. There are associated changes at the C3/4 level consistent with advanced discitis osteomyelitis.
Transverse Myelitis
Causes of transverse myelitis
viral infections: varicella zoster, herpes simplex, cytomegalovirus, Epstein-Barr, influenza, echovirus, human immunodeficiency virus
bacterial infections: syphilis, Lyme disease
post-infectious (immune mediated)
first symptom of multiple sclerosis (MS) or neuromyelitis optica (NMO)
Transverse Myelitis - Diagnosis: Example Question
A 45 year old previously fit and well man presents to the emergency department with worsening leg weakness. He is in full time employment as a brick layer and is normally very active. Over the last 24 hours he has started dragging his feet and feels unsteady when walking, describing his gait ‘like a drunk man’. On questioning he also describes increasing difficulty passing urine and has not had the sensation to empty his bladder for the past eight hours. He denies any preceding trauma, recent viral illness or similar previous symptoms in the past.
On examination he has normal muscle bulk and no fasciculations. There is symmetrical lower limb flaccid paralysis to the hips, with symmetrical hyporeflexia. He has a sensory level to T10 and is in urinary retention. Examination of the upper limbs and cranial nerves is entirely normal.
Which of the following would be the most useful initial investigation?
Aquaporin 4 antibodies Lumbar puncture > MRI spinal cord MRI brain HIV serology
This man presents with signs and symptoms of acute transverse myelitis. The underlying aetiological process can be diverse; it can be associated with underlying autoimmune systemic response, infectious cause or demyelinating process such as neuromyelitis optica.
The presence of a sensory level suggests a spinal cord lesion, as such a CT or MRI Brain would not be the first investigation. The most important initial approach in a patient presenting with acute disturbance of motor, sensory or autonomic function (and a sensory level) is to rule out a compressive cord lesion; an MRI spine is therefore an essential first step. Although HIV serology would be important in this patient, as aforementioned, the most important step is to exclude a compressive lesion.
Autonomic Dysreflexia
This clinical syndrome occurs in patients who have had a spinal cord injury at, or above T6 spinal level. Briefly, afferent signals, most commonly triggered by faecal impaction or urinary retention (but many other triggers have been reported) cause a sympathetic spinal reflex via thoracolumbar outflow. The usual, centrally mediated, parasympathetic response however is prevented by the cord lesion. The result is an unbalanced physiological response, characterised by extreme hypertension, flushing and sweating above the level of the cord lesion, agitation, and in untreated cases severe consequences of extreme hypertension have been reported.
Example Question:
You are called to a general medical ward during the night to review 48 year female who has become acutely agitated and confused. She came into hospital two days ago with a suspected urinary tract infection and has been making uneventful progress. She has a past history of traumatic spinal injury at level C5 three years ago with resulting spastic quadraparesis. On your arrival her blood pressure is 220/105 mmHg, heart rate is 55/min, and she is flushed and diaphoretic.
Of the following, what additional feature might you expect to find?
> Palpable bladder Ejection systolic murmur in the pulmonary area Flushing of the skin in the trunk and legs Relative afferent pupillary defect Complete heart block
This question is describing a case of autonomic dysreflexia. Of the options given, palpation of a distended bladder is likely and also diagnostic. Pulmonary murmurs can be a feature of the carcinoid syndrome. A relative afferent pupillary defect is seen with optic nerve pathology such as optic neuritis. Flushing of skin above the cord lesion is common due to parasympathetic feedback causing vasodilation but of course anything below the cord lesion remains vasoconstricted.
Transverse Myelitis vs MS - Example Question
A 17 year old Caucasian male with no past medical history presents with his first episode of sudden onset left leg weakness and numbness on his anterior left thigh, of sudden onset and persistent after 4 days. On examination, you note 3/5 weakness on flexion of his left hip and loss of sensation to light touch, pain and temperature on his anterior left thigh in the sensory nerve root L1 distribution. A contrasted MRI scan of the patients spine reveals a hyperintense T2 signal partially within the left side of the cord at the L1, with corresponding enhancement with gadolinium. No masses were observed. Further imaging of the brain is awaited. What is the diagnosis at present?
Multiple sclerosis Left spinal cord tumour Left anterior spinal ischaemic stroke > Left transverse myelitis Guillain Barre syndrome
The history, examination and radiological evidence are strongly suggestive of partial L1 transverse myelitis. The key question is whether this represents a diagnosis of multiple sclerosis (MS) or not. The diagnosis of MS is determined by the McDonald criteria, first proposed in 2001 and most recently revised in 20101. The lesions or clinical episodes suggestive of acute demyelinating episodes must be disseminated in both time and place. As a result, a patient presenting with only one symptomatic episode can be diagnosed with MS if their MRI scans demonstrate demyelinating plaques that are:
i) distinguished in age from the current symptomatic lesion
ii) In at least two of 4 areas typical of MS (periventircular, juxtacortical, infratentorial, spinal cord white matter).
In this case, only one episode in time and space has been demonstrated so far. Although a risk of future MS diagnosis is acknowledged, and may go on to be proven following MRI of the head, the diagnosis remains transverse myelitis at present.
It is often quoted that in patients diagnosed with transverse myelitis after their first symptomatic episode, only a small proportion go on to be diagnosed with MS later in their lives. However, more recent evidence suggest the pattern of transverse myelitis is important: only 5-10% of patients with complete transverse myelitis will be diagnosed with MS, with a viral febrile illness the most likely underlying cause. Patients with incomplete transverse myelitis have up to 72% risk of MS-consistent plaques found on MRI head, with 60-90% subsequently being diagnosed MS within 5 years2.
Old MS plaques appear better defined on T1 and T2 imaging than acute lesions. Contrast studies with gadolinium is also helpful: acute plaques tend to enhance to a greater degree on T1 imaging, correlated to acute inflammation that persists for up to 8 weeks and diminishes on treatment with glucocorticoids.
Brown-Sequard Syndrome
Brown-Sequard syndrome results from a lateral hemisection of the spinal cord. It presents with a loss of pain and temperature sensation on the side of the body contralateral to the lesion and a hemiplegia and loss of vibration sensation and proprioception on the ipsilateral side to the lesion.
Syringomyelia - Example Question
A 23-year-old university student presented with a year long history of occipital headache. This was worse on coughing, sneezing and straining and partially relieved by lying flat. On one occasion the headache had been associated with vomiting. She had previously consulted her family doctor who was treating her for migraine. Over the past two months she had noticed pain in her both arms and felt unsteady on her feet.
On examination touching her arms caused pain and there was reduced appreciation of pinprick and temperature sensation throughout both arms. Tone, power and reflexes in the upper limbs were normal. On testing upper limb co-ordination there was some past-pointing and a very mild intention tremor. On inspection of the feet there was pes cavus and Rombergs test was positive. Again tone, power and reflexes were normal in the lower limbs and plantars were downgoing. Proprioception was impaired with absent joint position sense until the level of the knee. Vibration sensation was impaired in both feet.
Given the clinical findings outlined above which of the following is the most likely diagnosis?
> Syringomyelia Friedrichs ataxia Brown-Sequard syndrome Charcot-Marie-Tooth disease Multiple sclerosis
Syringomyelia results from the formation of a fluid filled cavitation (called a syrinx) within the central canal of the spinal cord. The most common cause of a syrinx is obstruction to the flow of cerebrospinal fluid (CSF) by an Arnold Chiari malformation. An Arnold Chiari malformation is a developmental abnormality in which the cerebellar tonsils project through the foramen magnum and sit in a position which is normally occupied by the cervical spinal cord.
In this case the patient has features suggestive of an underlying Arnold Chiari malformation: occipital headache exacerbated by valsalva manoeuvre (coughing, sneezing and straining), pes cavus and cerebellar signs (past pointing and intention tremor in the upper limbs).
She also has features of an associated syringomyelia. The spinothalamic tracts are involved early in the process due to their decussation within the cord. This means that there is loss of pain and temperature sensation corresponding to the level of the syrinx. This often occurs in a shawl-like distribution. Hyperalgesia and allodynia are also seen in the upper limbs in some cases.
As the syrinx enlarges the dorsal columns are affected resulting in loss of proprioception and vibration sensation in the lower limbs. This explains the positive Rombergs test which indicates that there is a proprioceptive problem.
If the syrinx expands further the anterior horn cells can be affected resulting in wasting and weakness in the hands.
Friedrichs ataxia is an autosomal recessive inherited condition in which there is progressive ataxia, dysarthria, loss of proprioceptive and vibration sensation and weakness.
Brown-Sequard syndrome results from a lateral hemisection of the spinal cord. It presents with a loss of pain and temperature sensation on the side of the body contralateral to the lesion and a hemiplegia and loss of vibration sensation and proprioception on the ipsilateral side to the lesion.
Charcot-Marie-Tooth (also known as Hereditary Sensory and Motor neuropathy) encompasses a group of inherited conditions which present in mid-adult life with peripheral neuropathy. Patients commonly have pes cavus and often present with foot drop.
Multiple sclerosis (MS) can present in a variety of ways with cerebellar features, optic neuritis, paraesthesiae and tranverse myelitis all being reported. Although in theory many of the clinical features in this question could be explained by an underlying diagnosis of MS, the clinical presentation here is typical of syringomyelia secondary to an underlying Arnold Chiari malformation.
Neurofibromatosis T2 - Example Question
A 24-year-old woman is referred urgently to neurology for lower limb weakness. This has been getting gradually worse over the past 4 weeks and she is now experiencing problems walking.
She also complains of bilateral tinnitus which has been present for the past 3 months. This is associated with episodes of vertigo.
On examination both lower limbs have reduced power (3/5), with increased tone and hyperreflexia. The patient has one 1cm tan lesion on his torso but no other skin lesions are noted.
A MRI of his spine is requested:
SEE PASSMED MRI NF2
What is the most likely diagnosis?
Multiple sclerosis > Neurofibromatosis Von Hippel-Lindau disease Tuberous sclerosis Ataxia telangiectasia
This patient had neurofibromatosis type 2 (NF2). The MRI shows multiple tumours of the spinal cord in the context of the syndrome of multiple intracranial schwannomas, mengiomas and ependymomas.
Patients with NF2, in contrast to type 1, often have few skin changes. This patient had tinnitus due to the presence of bilateral acoustic neuromas.
The diagnostic criteria for NF2 are:
Bilateral vestibular schwannomas
A first degree relative with NF2 AND
Unilateral vestibular schwannoma OR
Any two of: meningioma, schwannoma, glioma, neurofibroma, posterior subcapsular lenticular opacities
Unilateral vestibular schwannoma AND
Any two of: meningioma, schwannoma, glioma, neurofibroma, posterior subcapsular lenticular opacities
Multiple meningiomas AND
Unilateral vestibular schwannoma OR
Any two of: schwannoma, glioma, neurofibroma, cataract
Subacute Combined Degeneration of the Cord (SCDC)
Basics
- due to vitamin B12 deficiency
- dorsal + lateral columns affected
- joint position and vibration sense lost first then distal paraesthesia
- upper motor neuron signs typically develop in the legs, classically extensor plantars, brisk knee reflexes, absent ankle jerks
- if untreated stiffness and weakness persist
SCDC Diagnosis- Example Question
55 year old cachetic male is brought into hospital after having been found on the floor by his sister, who visits him once a week. She reports a long history of depression and his appetite to have been poor for a number of years. He denies any loss of consciousness episodes, palpitations, chest pain, dysphagia or presyncopcal symptoms. When asked how he ended up on the floor, he vaguely reports to have slowly fallen from being generally weak and denies head injury. He does report a recent sore throat and dry cough. He is alert and orientated. On examination, he scores 3 and 4 out of 5 power in all movements. Lower limb reflexes could not be ilicited with a tendon hammer but bilateral upgoing plantars are noted. Which treatment might reverse the underlying condition most rapidly?
IV methylprednisolone IV immunoglobulin infusion Plasmophoresis IV thrombolysis > IM vitamin B12 + IV pabrinex
The patient presents with upgoing plantars and absent ankle jerks. This should alert all MRCP candidates to 5 classic diagnoses: subacute combined degeneration of the cord (SCDC), motor neurone disease, Friedrich’s ataxia, tabes dorsalis (syphilis) and dual peripheral with central pathology. In the context of cachexia and poor oral intake should alert a vitamin B12 deficiency, leading to a combination of peripheral and dorsal column degeneration, known as subacute combined degeneration of the cord. Vitamin B12 can in some cases reverse the neurology very rapidly.
Cervical Myelopathy
Cervical myelopathy is caused by narrowing of the cervical spinal canal, most commonly caused by stenosis. The aetiology includes:
Cervical cord tumours
ossification of the posterior longitudinal ligament
Trauma
Cervical degenerative changes (spondylosis)
Cervical degenerative disc disease
The investigation of choice and one which would enable you to asses spinal and foraminal stenosis would be cervical myelography or MRI of the cervical cord. Cervical myelography entails the use of contrast and can be nephrotoxic alas MRI is the preferred modality to image and diagnose cervical spondylosis.
Example Question:
You review an 80-year old retired teacher in your clinic in your clinic. She has been complaining of numbness on her arms and difficulty walking. On examination you find she has reduced sensation lateral aspect of her arms and forearms in the anatomical position. She has no wasting on the muscles of her hands. She has reduced biceps and supinator reflexes and reduced power bilaterally.
When she gets up to go you notice she has a scissoring gait which is wide based. You ask her to close her eyes and she is unable to stand still without support.
She lives on her own and usually is independent, although recently she has been struggling to cope. She has a background of hypertension and high cholesterol.
What is the most appropriate investigation to diagnose this lady?
Cervical myelography Cervical X-Ray Nerve conduction studies Nerve biopsy > MRI of the cervical cord
This lady has lower motor neuron deficit and sensory loss in her upper limbs at the level of C5-C7. She has spastic paraparesis, Romberg +ve indicating loss of proprioception in her lower limbs.
This presentation is suspicious of cervical myelopathy. The main segments which are affected of the cervical cord in this condition are C5-C7, as is the case in this lady. The dermatomal distribution of her sensory loss is confined to C5-C7 therefore supporting this hypothesis.
Lower Back Pain - Prolapsed Disc
Features - Leg pain usually worse than back pain and often worse on sitting
Usually produces clear dermatomal leg pain assoc w neurological deficits
L3 Nerve Root Compression:
- Sensory loss over anterior thigh
- Weak quadriceps
- Reduced knee reflex
- Positive femoral stretch test
L4 Nerve Root Compression:
- Sensory loss over anterior aspect of knee
- Weak quadriceps
- Reduced knee reflex
- Positive femoral stretch test
L5 Nerve Root Compression:
- Sensory loss over dorsum of foot
- Weakness in foot and big toe dorsiflexion
- Positive sciatic nerve stretch test
- Reflexes intact
S1 Nerve Root Compression:
- Sensory loss over posterolateral aspect of leg and lateral foot
- Weakness in plantar flexion of foot
- Reduced ankle reflex
- Positive sciatic nerve stretch test
Mx = Analgesia, Physio, Exercise and MRI
Spinal Cord Pathology - Putting it all together
MOTOR:
MND (ALS) = UMN + LMN signs
Poliomyelitis = LMNs - affects anterior horns
COMBINED MOTOR + SENSORY:
MS = ASYMMETRICAL
Varying Tracts - Motor + Sensory + Ataxia
SCDC:
1) Bilateral spastic paresis (corticospinal tracts)
2) Bilateral limb ataxia
3) Bilateral loss of proprioception and vibration sense (dorsal columns)
Friedrich’s Ataxia = Same as SCDC + SIGNIFICANT ATAXIA + INTENTION TREMOR + age of onset 10-15 (can be as late as 25) + ?FHx (not always) + IGT common
Brown-Sequard Syndrome:
1) Ipsilateral spastic paresis (Corticospinals)
2) Ipsilateral vibration and proprioception loss (Dorsal Columns)
3) Contralateral pain and temperature loss (Spinothalamic)
Anterior Spinal Artery Occlusion:
SUDDEN Weakness of legs = Vascular Causes
Eg Cocaine
1) Bilateral spastic paresis (Corticospinals)
2) Bilateral pain and temp loss (Spinothalamics)
Syringomyelia:
1) Flaccid Paresis - intrinsic muscles of the hand
2) Loss of Pain and Temp first
3) Loss of Vibration sense and Proprioception later
Hyperalgesia and Allodynia
SENSORY
Neurosyphilis - Loss of vibration sense and proprioception (dorsal columns)
Arnold Chiari Malformation + Syringomyelia
Syringomyelia results from the formation of a fluid filled cavitation (called a syrinx) within the central canal of the spinal cord. The most common cause of a syrinx is obstruction to the flow of cerebrospinal fluid (CSF) by an Arnold Chiari malformation.
An Arnold Chiari malformation is a developmental abnormality in which the cerebellar tonsils project through the foramen magnum and sit in a position which is normally occupied by the cervical spinal cord.
Features suggestive of an underlying Arnold Chiari malformation: occipital headache exacerbated by valsalva manoeuvre (coughing, sneezing and straining), pes cavus and cerebellar signs (past pointing and intention tremor in the upper limbs).
Features of an associated syringomyelia:
The spinothalamic tracts are involved early in the process due to their decussation within the cord. This means that there is loss of pain and temperature sensation corresponding to the level of the syrinx. This often occurs in a shawl-like distribution.
Hyperalgesia and allodynia are also seen in the upper limbs in some cases.
As the syrinx enlarges the dorsal columns are affected resulting in loss of proprioception and vibration sensation in the lower limbs = positive Rombergs test indicates that there is a proprioceptive problem.
If the syrinx expands further the anterior horn cells can be affected resulting in wasting and weakness in the hands.
Cervical Myelopathy - Presentation
This lady has lower motor neuron deficit and sensory loss in her upper limbs at the level of C5-C7. She has spastic paraparesis, Romberg +ve indicating loss of proprioception in her lower limbs.
This presentation is suspicious of cervical myelopathy. The main segments which are affected of the cervical cord in this condition are C5-C7, as is the case in this lady. The dermatomal distribution of her sensory loss is confined to C5-C7 therefore supporting this hypothesis.
