Medicine Dr. Akram

Neurology

“Diseases of the Spinal Cord”

Prof. Akram AI-Mahdawi

LECTURE 12

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Diseases of the Spinal Cord

- Prof Akram Al-Mahdawi

- CABM, MRCP, FRCP, FACP& FAAN

Objectives

To learn some basic anatomy of spinal cord

To have an idea about symptoms and signs of spinal cord

How would you approach a patient with spinal cord diseases?

Come across a common spinal cord diseases

Upper vs. Lower Motor Neuron

Upper motor neuron lesion (UMNL)

Motor cortex internal capsule brainstem spinal cord

Lower motor neuron lesion (LMNL)

Anterior horn cell nerve root plexus peripheral nerve

neuromuscular junction muscle

Basic Features of Spinal Cord Disease

UMN findings below the lesion

- Hyperreflexia and Babinski’s

Sensory and motor involvement that localizes to a spinal cord level

Bowel and Bladder dysfunction common

Remember that the spinal cord ends at about T12- L1

This box was added by the students for those who don’t know what these

abbreviations mean:

CABM: Certification of Arab Board of Medical Specialization

MRCP& FRCP: Member and Fellow of the Royal College of Physicians

FACP: Fellow of the American College of Physicians

FAAN: Fellow of the American Academy of Nursing

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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History

Onset

- Acute, subacute and chronic

Symptoms

- Pain

- Weakness

- Sensory

- Autonomic

Past history

Family history

Tempo of Spinal Cord Disease

Etiology Acute Subacute Chronic

Trauma X

Mass lesion X X

Infections X X X

Inherited X

Vascular X X X

Autoimmune X X

Nutritional X

This box was added by the students and it has been explained by Dr. Akram:

Before continuation you have to understand and review the spinal cord pathways (sensory and

motor): dorsal column& spinothalamic-sensory pathways- and corticospinal -motor pathway.

You can find series of 4 videos explaining these pathways on YouTube under the name of Spinal

pathways uploaded by Handwritten Tutorials.

Or you can find a summary page from (First Aid for USMLE step 1 version 2015) uploaded in

www.muhadharaty.com (Baghdad college of medicine 5th grade Neuromedicine

Prof. Akram Al.Mahdawi diseases of the spinal cord)

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Motor Exam

Upper cervical

- Quadriplegia with impaired respiration

Lower cervical

- Proximal arm strength preserved

- Hand weakness and leg weakness

Thoracic

- Paraplegia

Note: Tone -- Increased distal to the lesion

Sensory Exam

Establish a sensory level

- Dermatomes

Nipples: T4-5

Umbilicus: T8-9

Posterior columns

- Vibration

- Joint position sense (proprioception)

Spinothalamic tracts

- Pain

- Temperature

Autonomic disturbances

Neurogenic bladder

- Urgency, incontinence and retention

Bowel dysfunction

- Constipation more frequent than incontinence

With a high cord lesion, loss of blood pressure control

Alteration in sweating

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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The picture below was added by the students it is not included in the lecture:

Classical spinal cord syndromes

Anterior spinal artery infarct

Brown Sequard syndrome

Syringomyelia

Conus medullaris/caude equina lesions

Brown Sequard Syndrome

Cord hemisection

Trauma or tumor

Dissociated sensory loss

- Loss of pain and temperature contralateral to lesion, one or 2

levels below

crossing of spinothalamic tracts 1-2 segments above where they

enter

- Loss of vibration/proprioception ipsilateral to the lesion

these pathways cross at the level of the brainstem

Weakness and UMN findings ipsilateral to lesion

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Syringomyelia

Fluid filled cavitation in the center of the cord

Cervical cord most common site

- Loss of pain and temperature related to the crossing fibers occurs

early ((cape like sensory loss))

- Weakness of muscles in arms with atrophy and hyporeflexia.

- Ater – corticospinal tract involvement with brisk reflexes in the

legs, spasticity, and weakness

May occur as a late sequelae to trauma

Can see in association with Arnold Chiari malformation

Conus Medullaris vs. Cauda Equina Lesion

Finding Conus Medullaris Cauda Equina

Motor Symmetric Asymmetric

Sensory loss Saddle Saddle

Pain Uncommon Common

Reflexes Increased Decreased

Bowel/bladder Common Uncommon

Investigation of Spinal Cord Disease

Radiographic exams

- Plain films

- Myelography

- CT scan with myelography

- MRI

Spinal tap

- If you suspect: inflammation, MS and rupture of a vascular

malformation.

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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The picture below was added by the students it is not included in the lecture:

Spinal cord Dura matter

The figure above demonstrates the different locations of spinal cord tumors, (A)

Intramedullary tumors (B) Extramedullary – Intradural tumors (C) Extramedullary –

Extradural tumors.

Tumors

Metastatic or primary

- Extramedullary

Extradural (most common)

Bony, breast or prostate

Intradural (very rare)

Meninges - meningioma

Nerve root - schwannoma

- Intramedullary (very rare)

Metastatic

Primary - astrocytoma or ependymoma

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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B12 Deficiency

Subacute combined degeneration of the cord

B12 deficiency

- Malabsorption of B12 secondary to pernicious anemia or

surgery

- Insufficient dietary intake - vegan

Posterior columns and corticospinal tract involvement with a

superimposed peripheral neuropathy

Transverse myelitis

Inflammation of the spinal cord

- Post- infectious

- Post- vaccinial

- Multiple sclerosis

Pain at level of lesion may precede onset of weakness/sensory

change/bladder and bowel disturbances.

The picture above was added by the students it is not included in the lecture

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Infections Involving the Spinal Cord

Polio

- Only the anterior horn cells are infected

Tabes dorsalis

- Dorsal root ganglia and dorsal columns are involved

- Tertiary syphilis

- Sensory ataxia, “lightening pains”

HIV myelopathy

- Mimics B12 deficiency (Subacute combined degeneration of the

cord)

HTLV-1 myelopathy

- Tropical spastic paraparesis

Multiple Sclerosis

Demyelination is the underlying pathology

Cord disease can be presenting feature of MS or occur at any time

during the course of the disease

Lesion can be at any level of the cord

- Patchy

- Transverse

Devic’s syndrome or myelitis optica

- Transverse myelitis with optic neuritis

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Vascular Diseases of the Spinal Cord

Infarcts

Anterior spinal artery

- From atherosclerosis, during surgery in which the aorta is

clamped, dissecting aortic aneurysm

less often, chronic meningitis or following trauma

- posterior columns preserved (joint position sensation and

vibration)

- weakness (corticospinal tracts) and pain/temperature loss

(spinothalamic tracts)

Artery of Adamkiewicz at T10-11

Watershed area

- upper thoracic

Arteriovenous malformation (AVM) and venous angiomas

Both occur in primarily the thoracic cord

May present either acutely, sub acutely or chronically (act as a

compressive lesion)

Can cause recurrent symptoms

If they bleed:

- Associated with pain and bloody CSF

Notoriously difficult to diagnose

Hematoma - trauma, occasionally tumor

Other Disease of the Spinal Cord

Hereditary spastic paraparesis

- Usually autosomal dominant

Infectious process of the vertebrae

- TB, bacterial

Herniated disc with cord compression

- Most herniated discs are lateral and only compress a nerve root

Degenerative disease of the vertebrae

- Cervical spondylosis with a myelopathy

- Spinal stenosis

End

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Appendix (added by the students not included in the lecture):

The picture above summarizes the different locations of the spinal cord lesions.

Cases

Case (1)

A 19-year-old man is brought in to the emergency department after being stabbed in the back. He has no past medical history and takes no medications. Muscle strength is absent and tone is decreased in the right leg. The right patellar and Achilles reflexes are absent. Babinski sign is present on the right. There is a loss of vibratory sense and toe joint position on the right. There is a loss of pain and temperature sensation below T12 on the left. Which of the following will cause a loss of pain and temperature sensation on the left side, beginning at T12?

A. Damage to left-sided lateral spinothalamic tracts at T10 B. Damage to left-sided lateral spinothalamic tracts at T12 C. Damage to left-sided lateral spinothalamic tracts at L1 D. Damage to right-sided lateral spinothalamic tracts at T10 E. Damage to right-sided lateral spinothalamic tracts at T12

Diseases of the Spinal Cord Prof. Akram Al-Mahdawi

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Explanation:

The Brown-Sequard syndrome is associated with damage to the lateral spinothalamic tracts causing contralateral loss of pain and temperature sensation beginning two levels below the level of the lesion (remember that the spinothalamic tracts cross very early on in the spinal cord). Therefore, a lesion of the right-sided lateral spinothalamic tracts at T10 will result in a left-sided loss of pain and temperature sensation beginning at T12

So the answer is D

Case (2)

A 33-year-old white female comes to the office for the evaluation of weakness in her upper extremities. She thinks she is unable to feel pain or heat, because she recently noted some burn wounds on her fingertips, and does not know how she got them. She denies weakness in her lower limbs, as well as any history of trauma, headache, bowel or bladder problems, neck pain or facial pain. Examination reveals absent reflexes in her upper limbs. There is absent pain and temperature sensation on the nape of neck, shoulders and upper arms in a 'cape' distribution. Vibration and position sensations are preserved. Which of the following is the most likely pathology of the patient's condition?

A. Caudal displacement of the cerebellar tonsils and vermis B. Caudal displacement of the fourth ventricle C. Cord cavitation D. Focal cord enlargement E. Disc herniation and cord compression

Explanation:

The above patient is most likely suffering from syringomyelia. Areflexic weakness in the upper extremities and dissociated anesthesia (loss of pain and temperature with preserved position and vibration) in a "cape" distribution are classic findings of this condition. The pathology involves cavitary expansion of the spinal cord, which may produce myelopathy. There is destruction of the gray and white matter adjacent to the central canal. The most characteristic feature is the presence of a cord cavity, which usually communicates with the central canal of the spinal cord. The most frequent site of involvement is the lower cervical or upper thoracic region. When the syringes occur in the upper cervical cord and extend proximally to involve the medulla oblongata, the condition is called syringobulbia. Acquired causes of syringomyelia include trauma, inflammatory spinal cord disorders or spinal cord tumors. Occasionally, syringomyelia is idiopathic.

So the answer is C