MEDICAL NEURO quiz 5

Topics we will review in spinal cord, motor neuron, peripheral and NM disease week1

1. syringomyelia

2. Disc disease (cervial and lumbar)

3. Amyotrophic lateral sclerosis (ALS)

SC AND NM DISEASE CLINICAL APPROACH TO DISEASE OF SC: Gross anatomy

continuation of lower brainstem, ends at filum terminals

SC AND NM DISEASE CLINICAL APPROACH TO DISEASE OF SC: grey matter core and white matter tracts = what?

grey matter core= cell bodies

white matter tracts= myelinated tracts

SC AND NM DISEASE CLINICAL APPROACH TO DISEASE OF SC: Functional neuroanatomy

motor system =?

motor system= ipsilateral symptoms

1. corticospinal tracts (axons from cortex to spine synapse at anterior horn)

SC AND NM DISEASE CLINICAL APPROACH TO DISEASE OF SC: Functional neuroanatomy

1. sensory systems= ?

2. spinothalamic and dorsal column = ?

3. when is light touch affected?

sensory symptoms= contralateral symptoms

1. spinothalamic tracts= pain and temperature (and light touch)

2. dorsal columns= vibratory and proprioceptive (and light touch)

   1. light touch goes through both, so will not be affected UNLESS BOTH TRACTS ARE INVOLVED

SC and NM disease: spinal cord localization

In complete transection syndrome,

1. what systems are affected? where?

2. spinal shock from 1st minutes to first days of lesion=?

   1. what is after?

3. if at cervical level=?

4. if transaction below T1=?

1. both motor and sensory affected below level

2. spinal shock from 1st minutes to first days of lesion= complete absence and flaccid paralysis

   1. after, hyperreflexia with spastic paralysis

3. if at cervical level= tetraplegia

4. if transaction below T1= arms and hands spared

SC and NM disease: spinal cord localization

BROWN-SEQUARD SYNDROME

1. what syndrome?

2. what are symptoms

1. BROWN-SEQUARD SYNDROME (hemisection)

2. ipsilateral paralysis with contralateral pain and temperature loss

3. ipsilateral vibration with proprioceptive loss

SC and NM disease: spinal cord localization

CORD-ROOT SYNDROME (___)

1. affects what?

CORD-ROOT SYNDROME (extrinsic compression)

1. affects long tracts of the SC, from superficial to deep (lower extremities first)

SC and NM disease: spinal cord localization

Central Syndrome (___)

1. what type of distribution

1. (intramedullary)

2. cape-like distribution of anesthesia

SC and NM disease: spinal cord localization

Syndromes of CAUDA EQUINA and CONUS MEDULLARIS

1. what type of distribution

2. what is affected

1. patchy distribution, pain as cardinal symptom

2. bowel, bladder, and sexual function affected

SC and NM disease:

EFFECTs of damage to the motor functional atomic units of the SC

PICTURE 5

SYRINGOMYELIA: Background?

describes the presence of a “fluid-filled” cavity in the cord

SYRINGOMYELIA: Epidemiology

1. communicating (when CSF is being absorbed, i.e. hydrocephalus or

2. Non-communicating= more common of the 2, include Chiari I and II hindbrain malformations

SYRINGOMYELIA: clinical presentation

What are the 3?

1. syrinomyelia associated with hindbrain malformation

2. syrinx associated with spinal cord tumor

3. Post-traumatic syringomyelia

SYRINGOMYELIA: clinical presentation for

• syrinomyelia associated with hindbrain malformation (1)

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

SYRINGOMYELIA: clinical presentation for

• syrinx associated with spinal cord tumor (2)

1. intramedullary tumors= 4% of all CNS tumors, and syrinx is present in 20-50% of these

2. pain is the cardinal symptom, poorly localized to midline, deep aching pain

SYRINGOMYELIA: clinical presentation for

• post-traumatic syringomyelia (3)

1. years after initial injury

2. pain that increases with straining, head movement (initial phase)

3. paresthesias, weakness, and hyperhidrosis (later findings)

SYRINGOMYELIA: Diagnositc Evaluation (2)

1. clinical/symptoms as described

2. MRI

   1. if no signs of hindbrain malformations, history of trauma or extra medullary canal mass= administer contrast to search for spina cord tumor

SYRINGOMYELIA: Treatment =what involvement (6)

treatment= neurosurgical involvement

1. posterior fossa bony decompression with/without duraplasty, subpial tonsillar resection, lysis of adhesions, myelotomy and plugging of the obex

2. simple percutaneous aspiration of the syrinx

3. terminal ventriculostomy (sectioning of the terminal ventricles or proximal filum terminale

4. syrinx-to-subarachnoid shunts

5. syrinx-to-pertioneum shunts

6. subarachnoid-to-peritoneum shunts

SPONDYLOSIS AND DISC DISEASE

what disease?

Lumbar disease

• clinical features

• diagnosis/common lumbar root symptoms

PICTURE 8

SPONDYLOSIS AND DISC DISEASE

what aids in diagnosis

Clinical findings and MRI aaids in diagnosis

SPONDYLOSIS AND DISC DISEASE: treatment (4)

WHEN IS THE EXCEPTION TO TREATMENT…..(3)

1. 50% respond to non-surgical= always attempts 2-3 weeks of non-surgical management unless..

• symptoms of severe neurological deterioration

• cauda equina compression

• sphincter dysfunction

2. bed rest with lumbar flexure

3. analgesics, anti-inflammatory, muscle relaxants

4. when pain symptoms subside and after 3 weeks, initiate back exercises, instruction in posture

SPONDYLOSIS AND DISC DISEASE: what disease

CERVICAL DISEASE

PHOTO 10

SPONDYLOSIS AND DISC DISEASE: what is useful (2)

1. lateral and oblique x-ray films useful

   1. absolute measure of 14mm or less= narrow of canal

2. MRI useful however limited use when looking at bony anatomy

SPONDYLOSIS AND DISC DISEASE: treatment (2)

1. also manage non-surgically initially (as lumbar approach for medications useful)

2. workup important to determine level and cause of symptoms and if necessary treat underlying cause surgically with…

   1. anterior cervical discectomy with or without fusion

   2. posterior laminectomy and foraminotomy

   3. multiple anterior discectomies with fusion

   4. anterior corpectomy with fusion

   5. multiple level laminectomies

AMYOTROPHIC LATERAL SCLEROSIS (ALS)

Background (3)

progressive neurodegenerative moror neuron disease

1. glutamate mediated neurotoxicity

2. decreased capacity for handling oxidative stress

3. SOD1 gene mutation implicated in inherited disease

ALS epidemiology (3)

1. male v. female 2:1

2. 55-60 years onset average

3. 3-5 years lifespan post diagnosis

ALC clinical features (2/6)

1. lower motor neuron signs

   1. weakness, muscle wasting, fasciculations

2. upper motor neuron signs

   1. increased deep tendon reflexes, pseudobulbar features, extensor plantar responses, abnormal stretch reflexes

ALC clinical features (3-6)

3. most common symptoms early is arm weakness and a “claw-posture”

4. spreads regionally from distal to proximal

5. 25% present with foot drop

6. common bulbar symptoms: changes in clarity of speech and swallowing difficulties

ALS laboratory and evaluation differential diagnosis (4)

1. MRI rules out compressive SC disorder

2. Lead and mercury poisoning can mimic ALS

3. MRI of head rules out MS

4. Lyme disease with motor only symptoms can mimic ALS, so screen for Lyme

ALS Electrophysiologic features (1-2/3)

1. electromyography= fibrillation potentials

2. nerve conduction studies= slower conducing nerve fiber

ALS Electrophysiologic features 3/3

Diagnostic electrophyiologic criteria:

1. evidence of muscle degeneration should be diffuse

   1. fibrillation potentials and large motor units present in muscles of multiple extremities

   2. 3 out of 4 areas of neuroaxis with denervation (bulbar, thoracic, cervical, lumbosacral)

   3. no evidence of motor conduction block (an area of axon through which action potentials are not conducted)

   4. motor and sensory conduction velocity and amplitudes normal

ALS treatment (8)

1. Riluzole: prolongs survival of ALS patients, reduction of glutamate-mediated toxicity

2. vitamin E (shown to reduce onset of symptoms in mouse model of ALS)

3. creating (protective effect on mitochondria)

4. preventing pulmonary disability with assisted ventilation (at home preferably)

5. nutritional support

6. speech therapy

7. spasticity management

8. emotional well-being management

Spinal muscular atrophy: background (4)

1. lower motor neuron disorder

2. degenerative of anterior horn cells in the SC and bulbar motor nuclei

3. most common form linked to chromosome 5q13

4. most common cause of infantile death and second most common NM disorder (after Duchenne muscular dystrophy)

Spinal muscular atrophy: clinical features (4)

1. symmetric muscle weakness and atrophy of limbs

2. variable bulbar involvement

3. tremor

4. pathologic evidence of motor denervation

spinal muscular atrophy classification

PICTURE 18

Spinal muscular atrophy diagnostic criteria

picture 19