Peripheral Nerve Disorders the sequel

What are some causes of neuropathies in systemic disease?

• Diabetes

• Kidney disorders

• Autoimmune diseases

• Vitamin deficiencies & alcoholism

• Vascular disease

• Cancers

• Infections

• Inherited neuropathies

What is the most common form of neuropathy in the US?

DM I & II

What does DM cause neuropathy?

Loss of peripheral blood flow leads to ischemia in the distal nerve endings

What kind of neuropathy commonly results from DM?

Symmetrical distal poly neuropathy

What sensations are lost in sensorimotor neuropathy found in DM?

• Loss of vibration

• Pressure

• Pain

• Tempt

What locations is acute diabetic mononeuropathy commonly found?

• Carpal tunnel syndrome

• Cubital tunnel syndrome

• Peroneal n. At fibular head

• Lateral cutaneous nerve of thigh at inguinal ligament

What is diabetic autonomic neuropathy?

A widespread disorder of the autonomic fibers that leads to dysregulation of one or more of the following systems: cardiac, sexual, GI, sudomotor (sweating), pupillomotor (blurred vision), or bladder dysfunction

Why do chronic autoimmune conditions effect nerves?

Cuz they destroy joints, organs, and connective tissue which makes nerves vulnerable to compression injuries and entrapment

What nerves are damaged by Guillain-Barré syndrome?

• Motor

• Sensory

• Autonomic

What nerves are damaged by chronic inflammatory Demyelinating polyradiculopathy (CIDP)?

• Motor

• Sensory

What nerves are affected by multifocal motor neuropathy?

Motor

What vitamin deficiencies can cause neuropathies?

• E

• B1

• B6

• B12 (most common one to cause neuropathy as well as anemia)

• Niacin

• Thiamine

What percentage of long-term heavy alcohol users develop alcoholic neuropathy?

50%

What nutritional deficiencies can result from chronic alcohol use disorder and lead to neuropathy development?

• B12

• Thiamine

• Folate

Damage to nerves associated with long-term alcohol abuse may not be reversible when a person stops drinking alcohol. True or false?

True

What viruses would damage sensory nerves and result in sharp, lightening-like pain?

• Herpes varicella zoster (shingles)

• Epstein-Barr

• West Nile

• Cytomegalovirus

What kind of infections commonly results in sensory nerve damage?

Viruses

What kind of infections can result in extensive peripheral nerve damage?

• Bacterial

  • Lyme disease

  • Diphtheria

  • Leprosy (Hansen’s disease)

What effect does HIV neuropathy have on nerves?

• Rapidly progressive and painful poly neuropathy

  • Primarily of hands and feet

What is the most common type of inherited neuropathy?

Charcot-Marie-Tooth disease

You are seeing a pt for an eval who is direct access. The pt primarily reports difficulty with walking and with weakness in their legs. Upon inspection, you notice they have extremely high arches and hammertoes. When ambulating, they have foot drop and a steppage gait. They also present with 0’s on DTRs bilaterally on their LEs and diminished sensation bilaterally in their LEs. You note that their UEs score 5 or 4/5 on MMT whereas their LEs score 2+ or 3/5. What condition do they most likely have?

Charcot-Marie-Tooth disease

What conditions result from uremic toxicity and higher levels of ammonia in the blood?

Kidney disorders

How does vasculitis affect nerves?

It leads to loss of distal blood supply which will result in anoxic damage to distal nerve fibers

What are paraneoplastic syndromes?

The result of chemical signaling molecules by tumor cells by by an immune response to a tumor

If a specific drug is causing neuropathy, the neuropathy will commonly go away when the drug is discontinued or the dosage is changed. True or false?

True

What percentage of people who undergo chemo develop peripheral neuropathy

30-40%

When can chemotherapy induced peripheral neuropathy (CIPN) develop?

Right after the first treatment

What is the leading reason that people with cancer stop chemo?

CIPN

What movement system diagnoses’ can someone have who has a neuropathy condition?

• Force production (if main impact is on motor aspects)

• Sensory detection deficit

If someone has a sensory detection deficit, what might you observe during a STS?

• Failure during execution phase

• Hyperextension of the knee before hip extension

• Instability of ankle or stepping to alter BOS

If someone has a sensory detection deficit, what would you notice about their postural control?

• Unable or hard for them to stand unsupported

  • If they can stand unsupported, they will have significant increase in sway or LOB with eyes closed (EC)

• Limited improvement with practice

If someone has a sensory detection deficit, what might you notice about their gait?

• Variation in foot placement

• Hyperextension of knee during stance

• Loss of eccentric ankle control

• Assistance required

• Some improvement seen with visual guidance

• Always looking at their feet when walking

What can be effective to help reduce pain that often occurs with peripheral neuropathy?

• TENS

• Tricyclic antidepressants

• Anti-epileptics (gabapentin)

• SSRI/SNRIs

What modalities can make neuropathic pain worse or not help reduce it?

• Heat (makes it worse)

• Massage (does nothing for it)

At what percentage of one’s HR max and RPE should you do exercise at for someone with a peripheral neuropathy?

• 60-70% HR max

• 12-14 RPE

If someone has a radiculopathy, will there peripheral nerve conduction velocities be normal or abnormal?

Normal

In what muscle groups will you see EMG impairments if someone has a radiculopathy?

Paraspinals

What spinal regions are more likely to develop a radiculopathy?

• Cervical

• Lumbar

What are some causes of a plexopathy?

• Idiopathic

• Infectious or inflammatory

• Trauma

• Diabetic amyotrophy

• Entrapment neuropathy of the lumbosacral trunk during pregnancy

What functions are impaired with GBS?

• Motor function

• DTR

Most people who have GBS return to their prior lvl of function within what timeframe?

1 year

The incidence of GBS decreases with age. True or false?

False! It increases with age

2/3rds of those with GBS have what prior to the onset of their GBS symptoms?

• Respiratory or GI illness

  • Campylobacter jejuni

  • Cytomegalovirus

  • Varicella-zoster (herpes)

  • Epstein-Barr virus (mononucleosis)

  • Zika virus

  • COVID-19

  • Food poisoning

• While not the majority, some can have stressful events, surgeries, or vaccinations that precede GBS symptoms

GBS has been reported to develop (albeit at a statistically insignificant rate) after what vaccinations?

• Tetanus

• Hepatitis

• Influenza

What are the different types of GBS?

• Acute inflammatory Demyelinating polyradiculoneuropathy (AIDP)

• Acute motor axonal neuropathy (AMAN)

Describe AIDP GBS

When antibodies bind to myelin antigens and activates blood proteins (also known as complement) which results in damage to myelin

What is the most common type of GBS in the United States?

AIDP

Describe AMAN GBS

When immunoglobulin G antibodies bind to gangliosides on cell membranes of axons and activate blood proteins (also known as complement) that damages the axon

What percentage of people with GBS AIDP that are hospitalized require mechanical ventilation? Why?

20% of peeps cuz they have respiratory muscle weakness

What impairments/symptoms in GBS AIDP will make mechanical ventilation more likely?

• Rapid progression of symptoms

• UE weakness

• Autonomic dysfunction

• Bulbar paralysis

What percentage of people with GBS AIDP are unable to walk independently at their maximum level of weakness?

66%

What percentage of people with GBS AIDP are unable to walk 6 months after the onset of their symptoms?

20%

You are seeing a pt for the first time and for some reason, they don’t give you the patient’s diagnosis (so like the real world, right?!). Anywho, the pt presents with facial weakness, dysphagia, and dysarthria. During your eval, they also report a stocking/glove pattern sensory impairment in addition to severe, deep, aching pain when they try to move that’s even worse at night. They also let ya know, they are pretty constipated all the time, their BP fluctuates a lot, and they have a fib. What condition may they have?

GBS AIDP

What are the common S/S of GBS AIDP?

• CN crap

  • Facial weakness, oculomotor muscle weakness, dysarthria, dysphagia, vision problems

• Sensory involvement

  • Distal hyperesthesias, numbness, paresthesia, stocking/glove pattern

• Pain with movement that’s worse at night and described as severe, deep, aching, and cramping

• Autonomic stuff

  • Arrhythmias, orthostasis, BP instability, urinary retention, constipation, slowed GI motility

When trying to do some fun differential diagnosis between GBS AMAN and GBS AIDP, what’s a big give away?

GBS AMAN is MOTOR ONLY. If there’s any sensory, CN, or autonomic involvement, it’s gonna be GBS AIDP

GBS AMAN is strongly associated with what?

• Campylobacter jejuni and other GI problems

• Contaminated foot (raw poultry and raw milk)

Is GBS AMAN more common in older or younger peeps?

Younger

What season does GBS AMAN more commonly develop?

Summer

What will you see on an NCS if someone has GBS AMAN?

• Axonal poly neuropathy

• Normal sensory action potentials

What features need to be present for a diagnosis of GBS?

• Progressive weakness of 1+ limb that peaks within 4 weeks

• Absent or decreased DTRs in affected limb

What would you see in a CSF fluid analysis if someone has GBS?

• Elevated protein lvls by the end of the 2nd week

• Normal WBC

What NCV would you find if someone has GBS (this is present 80% of the time)?

• <60% normal velocity or blockage of nerve conduction

  • May take a few weeks to develop

• Prolonged distal motor latencies

• Temporal dispersion of CMAPs

  • CMAP amplitude will also decrease if AIDP

• F waves and H reflexes prolonged or absent

• Fibrillations

  • ONLY after 3-4 wks

• Abnormal motor recruitment on needle EMG with decreased recruitment and rapid firing motor units in weak muscles

  • ONLY in acute phase

Which structure more quickly regrows, myelin or axons?

Myelin

Even tho the mortality rate of GBS is pretty low (5%), what can cause death?

• Cardiovascular complications

• Respiratory complications

What percentage of people with GBS can walk UNAIDED at 6 months? What about at a year?

• 82% at 6 months

• 84% at 1 year

What percentage of people with GBS will recovery their FULL motor strength?

61%

What are some long term deficits that are commonly seen in those with GBS?

• Weakness in anterior tibialis, foot/hand intrinsics, quads, and glutes

• Fatigue/exhaustion

  • Due to dysautonomia or psychological consequences

• Pain and muscle aches with exertion

When someone is in the hospital for GBS, what things do you gotta try to prevent?

• VTE formation

• Skin breakdown

What is the primary medical management for GBS?

• IVIg

  • An IV infusion of immunoglobulin

If someone has GBS and is undergoing IVIg treatment, how many days do they receive this treatment?

5 days

How many weeks does it often take for GBS to hit its peak?

4 wks

What movement system diagnosis does someone with GBS typically get?

Force production deficit

What is the best rehab for someone with GBS? Why?

High intensity rehab cuz it minimizes disability and improves QoL

If you were seeing someone in the hospital with GBS, where would you recommend they be sent? Why?

• IPR

  • Cuz they need high intensity rehab and they get it at IPR (5 days/wk for 3 hr/day)

• OP

  • If they really want to get home, just gotta make sure they are able to go 1 hour/day

At what percentage of one’s HR max should someone with GBS be doing aerobic/endurance training?

65-90% HR max

You are seeing someone in the acute/progressive stage of GBS, what interventions may you wanna try?

• Respiratory care (postural drainage, chest percussion, respiratory inspiratory training)

• Early mobilization (bed positioning, ROM, stretching, functional activities, pressure relief)

• Pain management (TENS)

• Autonomic dysfunction regulation (compression stockings, abdominal binder)

What is the pattern of strength recovery in those with GBS?

Descending pattern (proximal to distal)

Which typically gains strength back first in someone with GBS, the arms or the legs?

The arms

How long does it take for strength to return for someone with GBS?

Weeks - months

When working with someone with GBS, you should give them as few breaks as possible to maximize improvements in their cardiopulmonary system. True or false?

False! Give em their darn breaks

When working with someone with GBS who is in the chronic/recovery stage, describe what exercise should look like

• Only working muscles that are 3/5 MMT or better

• Low reps, high frequency for short bouts

You are working with someone with GBS who is in the chronic/recovery stage. You just started their exercise program today but they are telling you it’s too easy. What should you do? Why?

Keep them where they are at. People with GBS can become fatigued and extremely sore quickly so you wanna wait 3-7 days before progressing

This is your first week treating your patient with GBS who is in the chronic/recovery stage. They seem to be killing it all week but when they come in Friday, they tell you they feel really weak and that they have been real sore since your last session. What should you do?

Hold off on exercise for a few days and when you start back up, start at a lower resistance or at a higher number of reps

What kind of muscle fibers are more commonly impacted in those with GBS? What kind of exercises should you do as a result?

• Fast-twitch muscle fiber recruitment

• Anything where you can focus on the speed or rise and fall in muscle force production (fast walking, jumping, lunging, etc.)

People with GBS often fatigue pretty quickly, that’s why ya take a lot of breaks during treatment. Since you’re a real smart PT (IF we make it through this hell of a semester), what kind of aerobic training may your pt benefit from to reduce fatigue?

Body weight supported treadmill training

What kind of disease is acute anterior poliomyelitis?

Viral disease (poliovirus)

How does acute anterior poliomyelitis enter the body? Where does it multiply?

• Enters the mouth

• Multiplies in the intestine

The majority of people with acute anterior poliomyelitis are asymptomatic. True or false?

True!

What peripheral neuropathy results in flu like symptoms? How long do they last?

25% of peeps with acute anterior poliomyelitis get it and it’ll last 2-5 days

What condition has a rare (<1%) asymmetric, flaccid paralysis of the UE and/or LE (LE more commonly)?

Acute anterior poliomyelitis

What age range most commonly develops acute anterior poliomyelitis?

0-3

Describe what structures are commonly affected by acute anterior poliomyelitis

• Inflammation of meninges and anterior horn cells

• Spinal and bulbar motor neurons get cooked

How many months after developing acute anterior poliomyelitis does someone’s recovery begin to plateau?

6-8 months

What factors determine the amount of recovery someone will have after acute anterior poliomyelitis?

• Number of motor neurons that recover and resume normal function

• Number of motor neurons that sprout axons to reinnervate muscle fibers left denervated by death of motor neurons (aka collateral sprouting)

• Degree of muscle hypertrophy wherein muscle fibers increase 2-3x normal size

How many muscle fibers does a single motor unit typically Innervate? What about in acute anterior poliomyelitis when collateral sprouting occurs?

• 100 normally

• 700-2000 with acute anterior poliomyelitis

Even though someone with acute anterior poliomyelitis has a significant reduction in total motor units, they at least have a normal interspersion of type I and II fibers, right? Or am I tweaking?

Tweaking, the normal interspersion of those fibers be diminished or absent

You are bout to a MMT with someone who has just recovered from acute anterior poliomyelitis. What results do you expect?

Normal MMT scores

When is the onset of post-polio syndrome (PPS) ?

15-40 years after the initial infection

What percentage of polio survivors who had paralysis will go on to develop PPS?

25-40%

What factors are associated with development PPS?

• Age greater than 10

• Prior hospitalization for acute polio

• Vent dependent at time of acute illness

• Weakness in all four extremities

• Rapid return of functional strength following extensive initial involvement