Spinal chord

Spinal cord & Spinal Nerves

The spinal cord (45cm long) is part of the central nervous system and is connected to the brain

Extends from the foramen magnum to the first lumbar vertebra (L1).

The spinal cord is the main pathway for information connecting the brain and peripheral nervous system.

31 pairs of spinal nerves

Spinal Cord Protection

Bony Canal- vertebral canal

Connective tissue- meninges

Cushion of cerebrospinal fluid (CSF)- CSF acts as a shock absorber

Meninges

The meninges surround, protect, & stabilize the CNS 

Consist of 3 layers DURAMATER ARACHNOID PIAMATER

Meninges

Epidural space- a space between bony canal & dura mater

Subdural space- A space between the dura mater & arachnoid mater- contains interstitial fluiid

Subarachnoid space- contains CSF fluid

Internal Anatomy of Spinal cord

Gray & white mater H- shaped gray

matter (central zone): dorsal & ventral horns

White matter (outer zone): - arrange in columns

Spinal Cord levels

The greatest amount of grey matter (cells) is largest in the

spinal segments of the cervical and lumbosacral enlargements

White mater (regions)

Anterior white column

Posterior white column

Lateral white column

Functions of spinal cord

Spinal cord reflexes: A reflex is a fast , involuntary, unplanned sequence of actions occur in response to a particular stimulus

Integration of information highway for upward and downward travel

of sensory and motor information

Classical spinal cord syndromesLesioned structures Causes

Complete sectionMielitisTrauma

Hemisection Brown-Séquard

Central structuresSyringomyeliaHydromyeliaTumor

Posterior columns and horns Tabes dorsalis

Posterior columns and lateral columns B12 deficiency

Classical spinal cord syndromesLesioned structures Causes

Dorsal columns, pyramidal tracts, spinocerebellar tract Spinocerebellar degeneration

Pyramidal tracts, anterior hornsALS

Anterior horn Spinal muscle atrophy,poliomyelitis

Pyramidal direct and crossed tracts Familial spastic paraparesis

Dorsal 1/3 of the spineOcclusion of the posterior spinal arteries

Anterior 2/3 of the spine Anterior spinal artery occlusion

Traumatic Spinal Cord Disease

10,000 new spinal cord injuries per year MVA, sports injuries the most common Victims under 30 yrs old, male>>females Fx/dislocation of vertabrae most likely to

occur at: C5,6 T12, L1 C1,2

Tumors

Metastatic or primary Extramedullary

Extradural - most common Bony - breast, prostate

Intradural - very rare Meninges - meningioma Nerve root - schwannoma

Intramedullary - very rare Metastatic Primary - astrocytoma or ependymoma

Centromedular formations

Intramedular tumors

Anterolateral column compression lead to sensory (thermoalgesic) loss that extends lower as the tumor grows

Lateral compression

Sensory disturbance appears first in the sacrate dermatoma; as the tumor grows, the sensory problems ascend upwards to the level of the lesion

Transverse myelitis

Inflammation of the spinal cord Post-infectious Post-vaccinial Multiple sclerosis

Pain at level of lesion may preceed onset of weakness/sensory change/b&b disturbance

Spinal tap may help with diagnosis

Infections Involving the Spinal Cord Polio

only the anterior horn cells are infected Tabes dorsalis

dorsal root ganglia and dorsal columns are involved tertiary syphillis sensory ataxia, “lightening pains”

HIV myelopathy mimics B12 deficiency

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

Vascular Diseases of the Spinal Cord

Infarcts Anterior spinal artery infarct

from atherosclerosis, during surgery in which the aorta is clamped, dissecting aortic aneurysm

less often, chronic meningitis or following trauma

posterior columns preserved (JPS, vib)

weakness (CST) and pain/temperature loss (spinothalamic tracts)

Artery of Adamkiewicz at T10-11 Watershed area

upper thoracic

Vascular Diseases of the Spinal Cord, cont Arteriovenous malformation (AVM)

and venous angiomas Both occur in primarily the thoracic

cord May present either acutely, subacutely

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 Diseases of the Spinal Cord Hereditary spastic paraparesis

Usually autosomal dominant Infectious process of the vertabrae

TB, bacterial Herniated disc with cord

compression Most herniated discs are lateral and

only compress a nerve root Degenerative disease of the

vertabrae Cervical spondylosis with a myelopathy Spinal stenosis

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

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 (AHC)

Later - CST 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

Syringomyelia

Conus Medullaris vs. Cauda Equina Lesion

Finding Conus CE

Motor Symmetric AsymmetricSensory loss Saddle SaddlePain Uncommon CommonReflexes Increased/ Decreased

decreasedBowel/bladder Common possible

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 CST involvement with a superimposed peripheral neuropathy

Friedreich’s disease

Degeneration of the long spinal

pathways (both ascending and

descending) and the peripheral nerve

fibers

Clinical presentation Gait abnormalities Ataxia Speech disorders Nistagmus Hyporeflexia Trophic changes

High plantar arches (pes cavus deformity of the foot)

Sensory disturbance Babinski sign

Clinical presentation Symptoms typically begin

sometime between the ages of 5 to 15 years,

scoliosis Diabetes (about 20% of people

with Friedreich's ataxia develop carbohydrate intolerance and 10% develop diabetes mellitus)

Heart disorders (e.g., atrial fibrillation, and resultant tachycardia (fast heart rate) and hypertrophic cardiomyopathy )

These symptoms are slow and progressive. Long-term observation shows that many patients reach a plateau in symptoms in the patient's early adulthood.

Genetics

Autosomal recesive disorder Mutation of frataxin gene (9q13-q21) Long arm of cromosome 9 Prevalence 1 : 50.000 Genetic counselling!

Treatment

Physical therapy Nerve and muscle trophic drugs Treatment of complications Treatment of heart disorders

Lateral Amiotrophic Sclerosis

Lateral Amiotrophic Sclerosis (ALS)

Degenerative disease of the central nervous system

Degeneration and death of motor neurons, both in the cortex and in the spine

Mean survival time is 3 to 4 years from diagnosis

USA – “Lou Gehrig’s disease”

ALS – clinical picture progressing motor deficit Signs related both to upper

and to lower motor neuron damage

starting age is around 60 years (20-80 years) Involvement of any part of the

CNS Either as UMN damage or as

LMN damage

SLA – clinical picture Muscle weakness

In 60-85% of pts starts in the limbs and in 15-40% starts with bulbar signs

Atrophy Stiffness Cramps Fasciculations;

Highly suggestive for ALS if largelly distributed and accompanied by UMN damage siogns

SLA – clinical picture Respiratory Insufficiency is seldom present

from the start Dispnea, asteny, weak cough, predisposition for

developping pneumonia ant athelectasies With time, LMN signs may overcome all of the UMN

signs Brainstem damage signs

disphagia disarthrie sialorrhea (reduction of swallowing) laringospasm Lately in the course of disease oculomotor problems

Criteriile El Escorial revăzute pentru diagnosticul sclerozei laterale amiotrofice

Criteriul de diagnostic Semne necesare

SLA sigură Semne ale NMC şi ale NMP în cel puţin 3 din 6 regiuni

SLA familială sigură Semne de afectare ale NMC şi NMP în o regiune (plus identificarea mutaţiei asociate prin procedee de laborator)

SLA probabilă Semne de afectare a NMC şi NMP în 2 din 6 regiuni (unele semne de NMC fiind rostral situate faţă de cele de NMP)

SLA probabilă, susţinută de testele de laborator

Semne de afectare ale NMC si NMP în o regiune (sau semne de laborator ale afectării NMC într-una sau mai multe regiuni plus proba EMG a denervării acute în 2 sau mai mulţi muşchi situaţi la nivelul a două sau mai multe membre)

SLA posibilă Semne de afectare ale NMC şi NMP în o regiune

ALS

EMG criteria for ALS (Lambert): Normal sensory conduction velocity Motor conduction velocities normal or nearly normal,

depending of the muscke waisting Fibrilation and fasciculations Increased amplitude and duration of action potentials

EMG is only accesory to diagnosis in ALS

Evaluation and follow up

Global evaluation scales for ALS: Scoring based on subjective and clinical data

Muscle force measuring Evaluation of quality of life

Treatment

Maintaining a good quality of life as long as possible

Prolongation of active life Prolongation of life expectancy

Drug Trials

Negative results Vitamin E TCH346 Celebrex Creatine Indinavir Topiramate(topamax) Neurontin Minocycline

Other drugs Lithium Arimoclomol Ceftriaxone Manganoporphirin

Medical ManagementRiluzole The only FDA approved drug for ALS

treatment Approved for use in the US, Europe- 1996

and Canada –2000 Safe, fairly well tolerated Moderate efficacy Expensive ($10,000/year !!)

Prolongs survival by 3-4 months, Cochran review 2005

Side effects include fatigue, nausea, diarrhoea and liver toxicity

Muscle weakness

Aerobics, exercises to improve flexibility, force As the disease progresses the rehabilitation

programme has to be adapted to possibilities Establish safe exercises without overexertion

Maintaining independence Assistive devices (wheel chair, cruches, walker,

voice command, lifts, large doors, adapted vehicles)

Symptomatic Management

Important part of ALS treatment Several recent advances for symptom

management Increase in survival and quality of life in

patients seen in ALS centers

Symptomatic Management Emotional lability (Pseudobulbar affect) Spasticity Cramps and Fasciculations

Difficult to treat generally -Magnesium –Slow Mag -Tonic water (quinine) -Chamomile tea ? -Low dose baclofen -Low dose benzodiazepines

Treatment of Pain Can occur at any stage in the disease Neuropathic, Musckulosketetal, immobility Combination of drugs NSAIDS, Gabapentin, Pregabalin, TCAs Severe Pain – Narcotics

Symptomatic Management

Treatment of Fatigue Amantidine – dose 100 mg Po twice or three

times daily Modafinil (Provigil)- 100 mg 1-2 times a day Treatment of other underlying causes ( thyroid dysfunction, anemia etc.)

Insomnia Bowel and Bladder Dysfunction

ALS Management Thick Mucus Production

Increase Hydration Guiafenesin (robitussin) liquid or pill form Propananol ? Suctioning and cough assist device

Management of Dysphagia

Sialorrhea Management Glycopyrrolate (Robunil)- 1-2 mg every 4 hours Benztropine, Amitriptyline Transdermal hyoscine patch Topical atropine drops - 1% every 4 hours Botox or Myobloc injection into the salivary glands Radiation therapy – if very severe (AAN Practice Parameter- R. G Miller and Colleagues, revised Nov, 2006)

Management of Respiratory Failure FVC checks every 3 months in clinic BIPAP if FCV < 50 PPV Invasive ventilation/Tracheostomy when FVC <

30 PPV Treating underlying infection Management of patient anxiety Early signs – sleep problems, morning

headache, ortopnea, shallow breath, speech problems, sigh

Palliative Care

Palliative services involved early Hospice for patients with end stage ALS Comfort care and pain management Early Decision making Advanced Directives