Lecture 3: Peripheral Neuropathies Flashcards
The UMN neuroanatomy consists of? (3)
- Cortex
- Brainstem
- Spinal cord (Spinal Tracts)
The LMN Neuroanatomy consists of? (4)
- Anterior Horn Cells/ Cranial Nerve Nuclei
- Spinal Nerve roots and Peripheral Nerves (Includes Cranial Nerves and Autonomic)
- Neuromuscular Junction
- Muscle
In the Peripheral nervous system, one can experience what 4 motor abnormalities?
- Weakness
- Fasciculations
- Atrophy
- Areflexia
In the PNS, one can experience what kind of sensory problems? (3)
- Peripheral Nerve = Cutaneous Loss
- Polyneuropathy= Stocking-glove pattern of loss
- Spinal nerve root= Dermatome Pattern
In the PNS, one can experience what autonomic dysfunctions? … (4)
- Flushing (redness)
- Changes in HR, SOB, BP
- Incontinence, Constipation, Diarrhea
- Dry eyes/mouth
Based on the classification of motor unit disorders, what 4 areas can be effected?
- Motor neuron disease (Cell Body)
- Peripheral Neuropathies (Axon and Myelin)
- Disease of the NMJ
- Primary muscle disease (Myopathies)
What are the cranial nerves responsible for eye movement?
CN III, IV, and VI
The nerve responsible for the Lateral rectus muscle is
CN VI Abducens
What cranial nerve is responsible for Superior Oblique?
CN IV Trochlear
What cranial nerve is responsible for superior rectus, inferior rectus, medial rectus, and inferior oblique?
CN III Oculomotor nerve
All parts of the peripheral nerve are necessary for signal transmission. What are the 4 major categories for nerve injury pathogenesis?
- Neuronal degeneration
- Wallerian Degeneration
- Segmental Demyelination
- Axonal Degeneration
A normal nerve consists of?
Nerve cell body
- > Nucleus
- -> Axon
- –> Intermode
- —> Node of Ranvier
- —-> Shawn Cell
- —–> Nucleus
- ——> Motor End Plate
- ——-> Muscle
What occurs with Wallerian Degeneration?
The distal segment of the nerve deteriorates and begins to make sprouts
What happens with segmental demyelination?
Portions of the nerve lose their myelination, but not all of the nerve
What happens with axonal degeneration?
Portions of the axon degenerate and begin one giant section lacking myelin
This is when the cell body experiences damage with degeneration of Axons
Neuronal Degeneration
This is damage to the axon at a specific point with distal degeneration
Wallerian Degeneration
This is injury to the myelin sheath without injury to the axon
Segmental Demyelination
This is diffuse axonal damage. The distal portion furthest from the cell body undergoes earliest and most severe change. It causes initial symptoms in hands and feet with gradual, proximal accent and continued injury
Axonal Degeneration
What are the 2 classifications of Neuropathy?
- Mononeuropathy
2. Polyneuropathy
What are the (3) causes of Mononeuropathy?
- Nerve Entrapment
- Repetitive Motion Injury
- Trauma
What are the (5) causes of Polyneuropathy?
- Infections Disease (HIV)
- Inflammatory Disease (ADIP/GBS, CIDP)
- Other systemic Disease (DM, Critical Illness, vitamin Deficiency)
- Genetic Disorders (Charcot Marie Tooth
- Toxins (therapeutic Drugs i.e. chemo, Alcohol)
What are the 7 general diagnostic approaches to determining Neuropathy?
- Comprehensive history gathering
- Family history, Recent diseases, Traumas, Lifestyle, Temporal features of symptoms (Rate of onset-Acute, Subacute, chronic), signs/symptoms (Sensory, Motor, Autonomic, or mixed), distribution (Distal vs. Proximal, symmetric, Asymmetric, or multifocal) - General Physical Examination
- Neurological examination focusing of diagnostic possibilities
- Blood studies
- Lumbar Puncture to R/O GBS/AIDP and CIDP
- EMG/NCV (Single most important diagnostic test for eval of neuropathy and can determine whether it is primary axonal, demyelinating, or mixed)
- Possible nerve Biopsy
This is classified as an Acute, Inflammatory, Demyelinating polyneuropathy.
Guillain-Barre Syndrome
What are the general considerations for Guillain-Barre syndrome?
- Annual incidence ranging from 1-2 cases per 100,000
- AIDP accounts for 85-90% of cases
- GBS is the most common cause of acute neuromuscular paralysis in developed Countries
- 2:1 male to female ratio
- Variants: Acute motor axonal neuropathy (AMAN) and Acute motor sensory axonal Neuropathy (AMSAN) (10%); Miller Fisher (3-5%)
_________ accounts for 85-95% of Gillian-Barre syndrome
AIDP
What is the most common cause of Acute Neuromuscular paralysis in developed countries?
GBS
What is the ratio of GBS in males and females?
Males 2:1 Females
What are the 3 variants to GBS?
- Acute motor axonal Neuropathy (AMAN)
- Acute Motor Sensory Axonal Neuropathy (AMSAN) (10%)
- Miller Fisher (3-5%)
What is the Etiology for Gillian-Barre Syndrome?
- Immune Mediated Disorder (Inflammatory)
2. Preceding infection in about 60% of cases
What is the pathogenesis to Gillian-Barre Syndrome?
- Affects Myelin of peripheral nerves (Preferential to motor)
- Demyelinating: Attacks myelin sheath sparing the nerve cell and sparing the axon in most cases
What is the typical disease course for GBS?
Inciting infection => 1-3 weeks until symptom onset ==> 1-4 weeks to reach Nadir ===> Plateau for 2-4 weeks ====> Recovery 1-2 years+
What are the signs and symptoms associated with GBS? (6)
- Initial Paresthesias, usually hands and feet
- Symmetric weakness with (usually) normal sensation
- Ascending weakness distal to proximal and possible autonomic
- Flaccid paralysis with diminished or absent reflexes
- CN Involvement, especially weakness of facial Muscles
- May require ventilation due to respiratory failure
What are the 5 key diagnostic studies for GBS?
- Imaging of spinal cord
- Lumbar Puncture (Electrophoresis)
- Elevated protein levels in CSF with normal cell count
- CSF protein concentration begins to rise a few days after onset of symptoms and peaks in 4-6 weeks - Blood Test (to test for infectious agents)
- EMG
- Decrease Motor Unit Recruitment = decreased interference pattern
- If damage, it may not show for up to 2 weeks due to the length of the nerve - NCV: Slowed, Often minimal sensory slowing, Prolonged distal latencies
What is the differential diagnosis for GBS? (5)
- Acute Spinal cord disease
- Brain stem ischemia
- Myasthenia Gravis
- Botulinum Intoxication
- CIDP
What is the Medical Management course for GBS? (2)
- Intravenous Immunoglobulin G (IVIG)
- Plasmapheresis
- One or the other, both does not = more benefit
- Steroids have failed to show benefits in the treatment of GBS
What is the prognosis for GBS?
Most patients with GBS return to normal function
How long till full recovery of motor strength occurs in GBS?
At one year, full recovery of motor strength occurs in about 60% of patients
How often does GBS occur in an individual?
Often a One-time episode. (Does not reoccur)
What % of patients do severe motor problems associated with GBS occur?
Severe motor problems persist in about 14% of patients with GBS
What are the 4 indicators for poor prognosis of GBS?
- Older Age
- Requiring Ventilation Support
- Rapid Progression (<7 Days)
- Axonal Injury
With respect to recovery from GBS, what typically occurs?
Schwann cells myelin repairs itself, but the nodes are more frequent making conduction less efficient that before the injury
What happens with respect to recovery from GBS in cases where he patient also has AMAN?
Collateral sprouting occurs in the earlier stages of recovery, but can create very large motor units
If axonal damage occurs from GBS, when does nerve regeneration occur?
Nerve regeneration occurs in the later stages if axonal damage occurred. Axonal regrowth occurs at a rate of 1mm/day
What is an ongoing issue with recovery of GBS?
Fatigue is an on going issue due to Giant Motor Units and less efficient nerve conduction
Clinical Management of GBS
What are the 5 things clinical should look for in a patient who may be presenting with GBS?
- Strength Deficits without sensory involvement ( <3 MMT)
- Areflexia
- Fatigue
- Pain
- No UMN Signs
Clinical management of GBS
How should clinicians intervene with patients who has GBS? (5)
- Functional training/Transfer training
- Family training and education
- Submax Exercise
- Monitor for signs of overworking/over stretching
- equipment assessment: order now vs waiting given prognosis
When should PT intervene with GBS if the disease is progressive and not stoppable?
At all stages.
What does a typical hospital course include for a patient recently diagnosed with GBS? (4)
- Acute Admission (Possible transfer to ICU if pt requires ventilation
- Inpatient Rehab
- Subacute or return home depending on status and family support
- Outpatient therapy
What is the incidence/Prevelenace of Chronic Inflammatory Demyelinating Polyneuropathy?
1.0-7.7 cases per 100,000 people
Men > women and those older than 50 years of age
What is the etiology of Chronic Inflammatory Demyelinating Polyneuropathy?
Autoimmune Inflammatory process
What is the pathogenesis of Chronic Inflammatory Demyelinating Polyneuropathy? (3)
- Demyelinating Nerves
- Same mechanism as GBS, but the progression is the key distinction (as well as sensory involvement)
- Often relapsing Unlike GBS
What are the key differences between GBS and Chronic Inflammatory Demyelinating Polyneuropathy?
- Both result in demyelination of the nerve
- Both have the same mechanism of injury
- Progression is the key distinction between GBS and CIDP
- CIDP is often relapsing unlike GBS
What does the typical time line look like for CIDP?
Disease course can occur with
- Stepwise progression with periods of plateau
- Steadily declining course
- Course with recurrent episodes
Describe what the timeline looks like for CIDP
- Insidious onset of symptoms >2 months
- Gradual progressive weakness may include LMN sensory, cranial, and autonomic dysfunction
- Treatment = stabilization/some improvement
- May be relapsing
What are the 4 signs and symptoms associated with CIDP?
- Gradual progressive weakness over at least 2 months
- Areflexia and flaccid Paralysis
- Can have involvement of motor, sensory, and autonomic dysfunction
- Cranial neuropathies and respiratory muscle weakness are rare, but possible
- Weakness may begin vocally, becoming bilateral or multifocal within a few months.
What are the 3 key diagnostic studies for determining if one has Chronic Inflammatory Demyelinating Polyneuropathy?
- EMG
- NCV
- LP (electrophoresis)
With CIDP, what are we looking for in an EMG?
Fibrillations
+) Sharp waves (Signs of Denervation
For CIDP, what are we looking for with NCV tests?
Slowed velocity both motor and sensory (Sensory more sensitive)
With CIDP, what are we looking for with LP (electrophoresis)
Elevated protein in CSF without increased in cell count
List the differential diagnosis for diagnosing CIDP? (8)
- Multifocal stroke
- Motor Neuron Disease
- Polyradiculopathy
- Inflammatory myopathy
- Neuromuscular junction disease
- DM, B12 deficiency
- Multiple sclerosis
- Tabes Dorsalis
What are the 5 key medical management protocols for when someone has CIDP?
- Prednisone
- Intravenous Immunoglobulin G (IVIG)
- Plasmapheresis
- Azathioprine
- Mycophenolate
What is the prognosis for CIDP?
Often associated with prolonged neurological disability
- May require an assistive device to walk and may progress to needed powered mobility
- 95% show improvement following Immunomodulatory therapy although the relapse rate is high unlike GBS
Clinical Management of CIDP?
What 5 signs and symptoms are therapists looking for to diagnose CIDP?
- Motor and sensory deficits (MMT <3
- Areflexia
- Fatigue
- Atrophy
- No UMN signs
Clinical management of CIPD
How should therapist intervene for someone with CIDP? (5)
- Functional training and strengthening
- Family training and education
- Monitor for signs of overworking.over-stretching
- Equipment assessment for adaptive equipment, assistive devices, braces, and/or wheelchairs (power/manual)
- energy conservation
What is the incidence/prevalence of Diabetic Neuropathy?
- DM is the most common cause of Neuropathy in the US. Approximately 50% of PT’s with DM will develop Neuropathy
What is the pathogenesis related to developing Diabetic Neuropathy?
High blood glucose causing a chain of metabolic changes which leads to Axonal Destruction
What is the pattern of development for Diabetic Neuropathy? (4)
- Distal symmetric sensorimotor neuropathy is most common
- Typical presentation (Stocking glove distribution). Distal to proximal
- Paresthesias, Dysethesias (Sensory)
- Later Weakness
What is the general pattern of weakness for a lesion in the cortex?
Contralateral Face and Body
What is the general pattern of weakness for a lesion in the Brainstem?
Ipsilateral face, Contralateral Body
What is the general pattern of weakness for a lesion in the spinal cord (SCI)?
At and below the level of the lesion
What is the general pattern of weakness for Polyneuropathy?
Distal > Proximal
What is the general pattern of weakness for NMJ issues?
Patchy, Face is common
What is the general pattern of weakness for Myopathy
Proximal > Distal
What is the timeline progression for DM?
Temporal
- Months to Years
- Insidious onset with continual progression
Describe the timeline for DM (4)
- Sensory loss distal hands and feet in months-years
- Weakness distal to proximal
- Possible Ulceration due to sensory loss
- Possible limb amputation
What are the Key Diagnostic studies for determining if someone has DM?
- Careful history and exam
- R/O other causes of Neuropathy
- Glucose tolerance test for those who do not have a prior history of DM
- EMG: Often see a combo (Acute denervation and re-innervation)
- NVC: Slowed conduction velocity (Motor and sensory)
- Sensory Always Before motor
EMG studies for DM often see a combo of Acute denervation and re-innervation. These include (3)…
- Fibrillations (Acute)
- Polyphasic and Giant motor units (Re-innervation)
- Chronic- May see changes in interference pattern
NCV studies for DM reveal slow conduction velocity for motor and sensory. Which of the two is effected first?
Sensory always before motor with DM
What is the differential diagnosis of DM (6 other considerations)
- All Chronic Sensorimotor Neuropathy
- All causes of Small-fiber neuropathy, autonomic neuropathy, rediculopathy, plexopathy, mononerupathy
- Myopathy
- Stroke
- CTS
- Cervical and lumbosacral Radiculopathy
What is the medical management protocol for DM (6)
- Optimal glucose control prevents and limits progression. (Not as likely to reverse existing neuropathy)
- Medications for neuropathic pain
- Diabetic foot care (Podiatrist/Orthotic, diabetic inserts and shoes)
- If autonomic symptoms present, referral to specialist (Urologist, Gastrointerologist, Cardiologist)
- Exercise
- Diet modification (Plant based diet)
Clinical Management of DM
PT’s should look for what signs and symptoms to rule in/out DM? (7)
- Sensory loss: Monofilament, vibration testing
- Poor lifestyle habits or other contributing factors
- Possible motor involvement
- R/O any other underlying pathology (No UMN signs)
- Pain
- Trophic changes, Blisters, Ulcers
- Balance issues
Clinical Management of DM
PT’s should intervene with a patient who presents with DM with (3)
- Education (Skin are and skin checks, exercise, diet/glucose management, fall prevention, prevention of further problems)
- Equipment assessment (Walking poles/assistive devices, footwear)
- Balance training
In order to rule in/out CNS and PNS involvement, one should…
Take a good history
Use the time line of events to help you determine the DX
Think about the pattern of symptoms and what is involved
- Motor, sensory, autonomic
- Stocking-glove, distal to proximal
What is the etiology for GBS?
Prior infection/event immune mediated inflammatory
What are the signs and symptoms associated with GBS? (3-4)
- Symmetric
- Ascending rapid flaccid paralysis
- (Distal to proximal)
- Areflexia
What key diagnostic tests should be performed to Rule In/out GBS? (3)
- EMG
- NCV
- LP (Electrophoresis)
What is the typical progression of GBS?
1-3 weeks after infection
1-4 weeks to peak (NADIR
2-4 weeks plateau
1+ year for full recovery
What medical management is required for GBS? (2)
IVIG
Plasmapheresis
What is the etiology of CIDP?
Unknown
Immune Mediated Inflammatory
What are the signs/symptoms associated with CIDP? (3)
- Gradual Motor loss
- Sensory Loss
- Areflexia
What key diagnostic tests are needed to rule in/out CIDP? (3)
- EMG
- NCV
- LP (Electrophoresis)
What is the typical progression of CIDP? (2)
- Symptoms over 2 months
2. (Some) Recovery/Replase
What is the medical management protocol for CIDP? (3)
- IVIG
- Plasmapheresis
- Steroids
What is the etiology of DM? (3)
- Prior Diabetes Mellitus
- Poor glucose control
- Metabolic
What are the signs and symptoms associated with Diabetic Neuropathy? (5)
- Numbness
- Dysenthesias
- Paresthesias
- Possible weaknsss
- Stocking-Glove (Distal > Proximal)
What key diagnostic tests are required to rule in/out DN?
- Glucose testing
- EMG
- NVC
What is the typical progression of Diabetic Neuropathy?
Month to Years
What is the medical management protocol for Diabetic Neuropathy?
Glucose management through…
-Diet and Exercise