SPINAL CORD, MOTOR NEURON, PERIPHERAL AND NEUROMUSCULAR DISEASE

Syringomyelia associated with Hindbrain Malformation

Difficulty using hands (weakness or loss of ability) and gait disturbance (weakness, stiffness or fatigue

What percentage of all CNS tumors are intramedullary tumors?

4%

What percentage of intramedullary tumors are associated with a syrinx?

25-50%

What is the cardinal symptom of a syrinx associated with spinal cord tumors?

Pain

How is the pain from a syrinx typically described?

Poorly localized to midline, deep aching pain

When does Post-traumatic Syringomyelia develop?

Years after an initial injury.

What are the initial symptoms of Post-traumatic Syringomyelia?

Pain that increases with straining and head movement.

What are the later findings of Post-traumatic Syringomyelia?

Paresthesias, weakness, and hyperhidrosis.

Communicating syringomyelia

when CSF is not being absorbed, i.e., hydrocephalus or hydromyelia

Non-communicating syringomyelia

more common of the 2, include Chiari I and II hindbrain malformations

Syringomyelia background

describes the presence of a"fluid-filled" cavity in the cord

What imaging technique is used to diagnose Syringomyelia?

MRI

What should be done if there are no signs of hindbrain malformation, history of trauma or an extramedullary canal mass in a Syringomyelia diagnosis?

Administer contrast to search for a spinal cord tumor.

Syringomyelia treatment (neurosurgical management)

• Posterior fossa bony decompression with/without duraplasty, subpial tosillar resection, lysis of adhesions, myelotomy and plugging of the obex.

• Simple percutaneous aspiration of the syrinx,

• Terminal ventriculostomy (sectioning of the terminal ventricles or proximal filum terminale)

What types of shunts are used in the treatment of syringomyelia?

• Syrinx-to-subarachnoid

• Syrinx-to-peritoneum

• Subarachnoid-to-peritoneum

Lumbar disease diagnosis

clinical findings and MRI

What percentage of patients respond to non-surgical treatment for lumbar disease?

50%

How long should non-surgical management be attempted before considering surgery for lumbar disease?

2-3 weeks

What are the symptoms that may warrant immediate surgical intervention in lumbar disease?

Severe neuro deterioration, cauda equina compression, sphincter dysfunction

What is a recommended initial treatment for lumbar disease?

Bed rest with lumbar flexure

What types of medications are commonly used in the treatment of lumbar disease?

Analgesics, anti-inflammatory drugs, muscle relaxants

What should be initiated after pain symptoms subside and after 3 weeks of treatment for lumbar disease?

Back exercises and instruction in posture

What imaging techniques are useful for diagnosing cervical disease?

Lateral and oblique x-ray films

What measurement indicates a narrow cervical canal?

An absolute measurement of 14mm or less

Is MRI useful for diagnosing cervical disease?

Yes, but it has limited use when looking at bony anatomy

What is the initial management approach for cervical disease treatment?

Non-surgical management.

What is important to determine during the workup for cervical disease?

The level and cause of symptoms.

What surgical procedures are used as necessary to treat the underlying causes of cervical disease?

• Anterior cervical discectomy with or without fusion

• Posterior laminectomy and foraminotomy

• Multiple anterior discectomies with fusion

• Anterior corpectomy with fusion

• Multiple level laminectomies

What is Amyotrophic Lateral Sclerosis (ALS)?

• progressive neurodegenerative motor neuron disease

• Glutamate mediated neurotoxicity

• Decreased capacity for handling oxidative stress

• SOD1 gene mutation implicated in inherited disease

ALS Epidemiology

• Male vs female 2:1

• 55-60 years onset average

• 3-5 years lifespan post diagnosis

Lower motor neuron signs of ALS

Weakness, muscle wasting, fasciculations

Upper motor neuron signs of ALS

Increased deep tendon reflexes, pseudobulbar features, extensor plantar responses, abnormal stretch reflexes

Most common early symptom of ALS

arm weakness and a "claw-posture"

In what pattern does ALS spread within the body?

regionally from distal to proximal

What percentage of ALS patients present with foot drop?

25%

What are common Bulbar symptoms associated with ALS?

changes in clarity of speech and swallowing difficulties

What differential diagnoses of ALS does an MRI rule out?

Compressive SC disorder, MS (MRI of head)

Which poisonings can mimic ALS symptoms?

Lead and mercury poisoning

Which disease with what kind of symptoms can mimic ALS and should be screened for?

Lyme diseasemotor-only symptoms

Electrophysiologic features of ALS

• Electromyography = fibrillation potentials

• Nerve conduction studies = slower conducting nerve fibers

What is a key diagnostic criterion for ALS regarding muscle denervation?

Evidence of muscle denervation should be diffuse.

What types of potentials and units should be present in multiple muscles for ALS diagnosis?

Fibrillation potentials and large motor units.

How many areas of the neuroaxis must show denervation for ALS diagnosis?

3 out of 4 areas (bulbar, thoracic, cervical, lumbosacral).

What should be absent in the diagnosis of ALS related to motor conduction?

No evidence of motor conduction block.

What should be normal in terms of conduction for ALS diagnosis?

Motor and sensory conduction velocity and amplitudes.

What is the role of Riluzole in ALS treatment?

Prolongs survival of ALS patients and reduces glutamate-mediated toxicity.

What effect does Vitamin E have in ALS treatment?

Shown to reduce the onset of symptoms in a mouse model of ALS.

What is the role of Creatine in ALS treatment?

Has a protective effect on mitochondria.

How can pulmonary disability be prevented in ALS patients?

With assisted ventilation, preferably at home.

What type of support is important for ALS patients?

Nutritional support.

What therapy can help ALS patients?

Speech therapy.

2 types of management used in ALS treatment

• Spasticity management

• Emotional well-being management

What type of disorder is Spinal Muscular Atrophy?

Lower motor neuron disorder

What cells degenerate in Spinal Muscular Atrophy?

Anterior horn cells in the spinal cord and bulbar motor nuclei

Which chromosome is the most common form of Spinal Muscular Atrophy linked to?

Chromosome 5q13

What is spinal muscular atrophy the most common cause of?

infantile death

What is spinal muscular atrophy the second most common of?

neuromuscular disease (second to Duchenne's muscular dystrophy)

What are the clinical features of spinal muscular atrophy related to muscle strength?

Symmetric muscle weakness and atrophy of limbs

What type of involvement can occur in spinal muscular atrophy?

Variable bulbar involvement

What is a common symptom of spinal muscular atrophy that involves involuntary movements?

Tremor

What type of pathological evidence is associated with spinal muscular atrophy?

Pathologic evidence of motor denervation

What is a key feature of spinal muscular atrophy related to muscle weakness?

Symmetrical muscle weakness, proximal greater than distal.

What muscle involvement is observed in severe cases of spinal muscular atrophy?

Trunk muscles involved, with poor head and trunk control.

What type of weakness is present in spinal muscular atrophy, specifically regarding intercostal muscles?

Intercostal weakness, but sparing of the diaphragm.

What are the clinical signs of denervation in spinal muscular atrophy?

Fasciculations or tremor.

What laboratory tests can provide evidence of denervation in spinal muscular atrophy?

EMG or muscle biopsy.

What is a clinical exclusion criterion for spinal muscular atrophy related to the central nervous system?

CNS dysfunction

What is a clinical exclusion criterion for spinal muscular atrophy that involves joint deformities?

Arthrogryposis

What is a clinical exclusion criterion for spinal muscular atrophy that involves issues with other organ systems?

Abnormalities of other organ systems

What is a clinical exclusion criterion for spinal muscular atrophy related to the sense of touch?

Sensory loss

What is a clinical exclusion criterion for spinal muscular atrophy involving muscle weakness in the face or eyes?

Severe facial or extraocular muscle weakness

What is a clinical exclusion criterion for spinal muscular atrophy that indicates increased muscle tone or reflexes?

Hypertonia or hyperreflexia

What is one laboratory exclusion criterion for spinal muscular atrophy?

High creatine kinase

What is another laboratory exclusion criterion for spinal muscular atrophy?

Aminoaciduria

What is a laboratory exclusion criterion for spinal muscular atrophy related to organic compounds?

Organic aciduria

What enzyme deficiency is a laboratory exclusion criterion for spinal muscular atrophy?

Hexosaminidase A or B deficiency

What condition related to blood proteins is a laboratory exclusion criterion for spinal muscular atrophy?

Monoclonal gammopathy

What type of biopsy evidence is a laboratory exclusion criterion for spinal muscular atrophy?

Biopsy evidence of lipid or glycogen storage disease or mitochondrial abnormality

What nerve conduction characteristic is a laboratory exclusion criterion for spinal muscular atrophy?

Abnormally slow nerve conduction velocity