Peripheral Nerves and Neuropathies Flashcards by Benjamin Kozak

Functional Organization of PNS

PNS is divided into two divisions, what are they = ?

Peripheral Nerves & Neuropathies

Functional Organization of PNS:

- PNS is divided into two divisions:

Sensory (afferent) Division
Motor (efferent) Division

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Functional Organization of PNS

PNS - Sensory (afferent) division relays what information ?

Peripheral Nerves & Neuropathies

Functional Organization of PNS:

- PNS - Sensory (afferent) division information;

(1) Somatic Sensory :

General: Touch, pain, pressure, vibration, temp, and propriception in skin, body wall, and limbs.
Special: Hearing, equilibrium, vision.

(2) Visceral Sensory :

General: Stretch, pain, temp, chemical changes, and irratiation in viscera; nausea and hunger.
Special: Taste, smell

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Functional Organization of PNS

Motor (efferent) division relays what information ?

Functional Organization of PNS:

- Motor (efferent) division information;

(1) Somatic Nervous System:

Motor innervation of all skeletal muscles.

(2) Autonomic Nervous System (ANS):

Motor innervation of smooth muscle, cardiac muscle, and glands.

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Functional Organization of PNS

Two divisions of ANS

Functional Organization of PNS:

- Two divisions of ANS =

Sympathetic
Parasympathetic

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Peripheral Nervous System (PNS)

Includes = ?

3 things

Peripheral Nerves & Neuropathies

Peripheral Nervous System (PNS) includes:

Cranial nerves
Spinal nerves
Peripheral nerves

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Peripheral Nerves

Supply both the _ ? _ , and _ ? _ structures.

Peripheral Nerves & Neuropathies

Peripheral Nerves:

Supply both the viscera ( autonomic ), and somatic structures.

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Peripheral Nerves

Peripheral nerves are usually mixed: consisting of the _ ? _ , _ ? _ , and _ ? _ axons.

Peripheral Nerves & Neuropathies

Peripheral Nerves:

Peripheral nerves are usually mixed: consisting of the sensory , autonomic , and motor axons.

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Peripheral Nerves

Peripheral axons are classified according to _ ? _ , and _ ? _ of conduction

Peripheral Nerves & Neuropathies

Peripheral Nerves:

Peripheral axons are classified according to diameter , and speed of conduction (e.g., Ia, Ib, II, Adelta, and C).

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Plexus and nerves…

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Cervical region / Anterior (ventral) division = ?

Peripheral Nerves & Neuropathies

Plexus & Nerves:

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Cervical region / Anterior (ventral) division = Cervical plexus, brachial plexus

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Plexus and nerves…

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Thoracic region /Anterior division = ?

Peripheral Nerves & Neuropathies

Plexus & Nerves:

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Thoracic region /Anterior division = Intercostal nerves

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Plexus and nerves…

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Lumbar region / Anterior division = ?

Peripheral Nerves & Neuropathies

Plexus & Nerves:

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Lumbar region / Anterior division = Lumbar plexus, Sacral plexus

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Plexus and nerves…

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Sacral region = ?

Peripheral Nerves & Neuropathies

Plexus & Nerves:

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Sacral region = Sacral plexus, Lumbosacral plexus

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Plexus and nerves…

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Coccygeal region = ?

Peripheral Nerves & Neuropathies

Plexus & Nerves:

- The ventral rami innervates skin and muscles on the anterior aspect of the trunk, limbs, also provide the spinal contributions to all major neural plexuses.

- As such, they are responsible for the majority of the body’s sensorimotor innervation:

Coccygeal region = Coccygeal plexus

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Cervical Plexus

Anterior rami of = ?
Provides cutaneous sensory information from the _ ? _ to the _ ? _.
Innervates the _ ? _ muscles, and _ ? _.

Peripheral Nerves & Neuropathies

Cervical Plexus:

Anterior rami of C1 - C4
Provides cutaneous sensory information from the posterior scalp to the clavicle.
Innervates the anterior neck muscles, and diaphragm .

Cutaneous Sensory Information

The information that the skin sends to the central nervous system about touch , pressure , vibration , temperature , and pain .

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Brachial Plexus

Anterior rami of ? - T1
Entire _ ? _ is innervated by the brachial plexus branches.

Peripheral Nerves & Neuropathies

Brachial Plexus:

Anterior rami of C5 - T1
Entire upper limb is innervated by the brachial plexus branches

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Lumbar Plexus

Branches innervate the skin and muscles of the _ ? _ and _ ? _ .

Peripheral Nerves & Neuropathies

Lumbar Plexus:

Branches innervate the skin and muscles of the anterior and medial thigh .

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Sacral Plexus

Innervates the ? , as well as, most of the ? and ?.

Peripheral Nerves & Neuropathies

Sacral Plexus:

Innervates the posterior thigh , and most of the leg & foot .

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Peripheral Nerves

Consist of parallel bundles of axons (neurons) surrounded by three connective tissue sheaths:

? = Separates individual axons.
? = Surrounds bundles of axon (fascicles).
? = Encloses the entire nerve trunk.

Peripheral Nerves & Neuropathies

Peripheral Nerves:

- Consist of parallel bundles of axons (neurons) surrounded by three connective tissue sheaths:

Endoneurium = Separates individual axons.
Perineurium = Surrounds bundles of axon (fascicles).
Epineurium = Encloses the entire nerve trunk.

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Signs of peripheral damage

Include:

= _ ? _ changes
= _ ? _ changes
_ ? _ changes
= ?

Peripheral Nerves & Neuropathies

Signs of peripheral damage =

Sensory changes
Autonomic changes
Motor changes
Denervation : trophic changes

Trophic changes are abnormalities
that affect the area of pain, such as:

Wasting of the skin, tissues, or muscle
Thinning of the bones
Changes in hair or nail growth
Pitting of the nails
Increased or decreased hair growth in the limb
Changes in skin tone
Changes in skin texture

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Nerve Injury – What’s Happening?

Class I = ?

Type A = ?
Type B = ?

Peripheral Nerves & Neuropathies

Nerve Injury – What’s Happening:

Class I

Neurapraxia

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Nerve Injury – What’s Happening?

Class II = ?

Peripheral Nerves & Neuropathies

Nerve Injury – What’s Happening:

Class II

Axonotmesis

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Nerve Injury – What’s Happening?

Class III = ?

Peripheral Nerves & Neuropathies

Nerve Injury – What’s Happening:

Class III

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Nerve Injury – What’s Happening?

Class IV = ?

Peripheral Nerves & Neuropathies

Nerve Injury – What’s Happening:

Class IV

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Nerve Injury – What’s Happening?

Class V = ?

Peripheral Nerves & Neuropathies

Nerve Injury – What’s Happening:

Class V

Neurotmesis

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# Traumatic Injury to a Peripheral Nerve - ***Mononeuropathy*** Depending on the severity of damage, traumatic injuries to peripheral nerves are classified into three categories: 1. = **?** 2. = **?** 3. = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Mononeuropathy**: 1. Traumatic myleinopathy 2. Traumatic axonopathy 3. Traumatic severance

# Classification of Neuropathies - **Mononeuropathy** **-** Neuropathy = Mononeuropathy (***Traumatic myleinopathy*** ) * Usual Cause = **?** * Pathology = **?** * Typical Recovery = **?** ## Footnote *Peripheral Nerves & Neuropathies*

Neuropathy = Mononeuropathy (***Traumatic myleinopathy*** ) * **Usual Cause** = Trauma * **Pathology** = Demyelination * **Typical Recovery** = Complete and rapid by remyelination

# Classification of Neuropathies - **Mononeuropathy** **-** Neuropathy = Mononeuropathy (***Traumatic axonopathy*** ) * Usual Cause = **?** * Pathology = **?** * Typical Recovery = **?** ## Footnote *Peripheral Nerves & Neuropathies*

Neuropathy = Mononeuropathy (***Traumatic axonopathy*** ) * **Usual Cause** = Trauma * **Pathology** = Axonal damage * **Typical Recovery** = Slow by regrowth of axons, complete because Schwann cells and connective tissue sheath remain intact.

# Classification of Neuropathies - **Mononeuropathy** **-** Neuropathy = Mononeuropathy (***Traumatic severance*** ) * Usual Cause = Trauma * Pathology = **?** * Typical Recovery = **?** ## Footnote *Peripheral Nerves & Neuropathies*

Neuropathy = Mononeuropathy (***Traumatic severance*** ) * **Usual Cause** = Trauma * **Pathology** = Axon and myelin degeneration * **Typical Recovery** = Slow with poor results

# Classification of Neuropathies **-** Neuropathy = ***Multiple Mononeuropathy*** * Usual Cause = **?** * Pathology = **?** * Typical Recovery = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**-** Neuropathy = ***Multiple Mononeuropathy*** * **Usual Cause** = Complication of blood vessel disease / inflammation / diabetes * **Pathology** = Ischemia of neuron * **Typical Recovery** = Slow by regrowth of axons

# Classification of Neuropathies **-** Neuropathy = ***Polyneuropathy*** * Usual Cause = **?** * Pathology = **?** * Typical Recovery = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**-** Neuropathy = ***Multiple Mononeuropathy*** * **Usual Cause** = Complication of diabetes/ autoimmune disorder (GBS) or genetic. * **Pathology** = Metabolic or inflammatory * **Typical Recovery** = Diabetic neuropathy may be stable, progressive or improve with better blood glucose control; GBS improves gradually; hereditary is slow progressive.

# Mononeuropathy Focal neuropathies are conditions in which you typically have damage to a single nerve; most often in the... * _ **?** _ , * _ **?** _ , * _ **?** _ , * _ **?** _ ## Footnote *Peripheral Nerves & Neuropathies*

**Mononeuropathy**: * Focal neuropathies are conditions in which you typically have damage to a single nerve; most often in the ***hand*** , ***head*** , ***torso*** , or ***leg*** . * This type of nerve damage is ***less common***

# Traumatic Myelinopathy **-** Refers to the loss of myelin limited to the site of injury. * Peripheral myelinopathy interferes with the function of _ **?** _ . ## Footnote *Peripheral Nerves & Neuropathies*

Mononeuropathy - **Traumatic Myelinopathy**: **-** Refers to the loss of myelin limited to the site of injury. * Peripheral myelinopathy interferes with the function of ***large-diameter axons*** (***light touch*** / ***proprioceptive deficits*** ).

Focal compression of a peripheral nerve causes = _ **?** _ ## Footnote *Peripheral Nerves & Neuropathies*

Mononeuropathy - **Traumatic Myelinopathy**: **-** Focal compression of a peripheral nerve causes ***traumatic myelinopathy*** . * Repeated mechanical stimuli may cause focal compression.

Myelinopathy Prognosis = **?** ## Footnote *Peripheral Nerves & Neuropathies*

Mononeuropathy - **Traumatic Myelinopathy**: * **Myelinopathy Prognosis** = Good in cases of focal compression * Schwann cells can remyelinate ## Footnote Mononeuropathy

Traumatic _ **?** _ , results in Wallerian degeneration. ## Footnote *Peripheral Nerves & Neuropathies*

Mononeuropathy / **Traumatic Axonopathy** - Axon Damage: * Disrupts ***axons*** and results in ***[Wallerian degeneration](https://www.sciencedirect.com/topics/neuroscience/wallerian-degeneration#:~:text=Wallerian%20degeneration%20is%20disruption%20of,to%20develop%20on%20needle%20EMG.)***. * Occurs distal to the lesion ## Footnote Mononeuropathy

Axonopathies affect all sizes of axons; reflexes, somatosensorial, and motor functions are significantly _ **?** _ . ## Footnote *Peripheral Nerves & Neuropathies*

Mononeuropathy / **Traumatic Axonopathy** - Axon Damage: * Axonopathies affect all sizes of axons; reflexes, somatosensorial, and motor functions are significantly ***reduced*** or absent * Regenerating axons (axon regrowth) may re-innervate targets

# Axon Repair * Prognosis improved if = **?** * Axonal regrowth, how much per day / month **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Axon Repair**: **-** Prognosis improved if ***support structures intact***. * *Endoneurium* , *Perineurium* , *Epineurium* **-** Axonal regrowth: ***1-2 mm*** / ***day*** , ***1 inch*** / ***month*** . ## Footnote * ***Axonal Sprouting*** : Intact axons take over, results in changes in motor unit morphology.

# Traumatic Severance _ **?** _ , and _ **?** _ are completely interrupted, causing immediate loss of sensation and/or muscle paralysis in the area supplied. ## Footnote *Peripheral Nerves & Neuropathies*

***Traumatic Severance***: **-** Occurs when nerves are physically divided by excessive stretching or a laceration. * ***Axons*** and ***connective tissue*** are completely interrupted, causing immediate loss of sensation and/or muscle paralysis in the area supplied. * Wallerian degeneration begins, later axons in the proximal stumps begin to sprout. * Regeneration, however, may not always be functional, if the sprouts reach inappropriate targets or end-organs, resulting in poor recovery

# Repair of Severance * Requires = **?** * Prognosis typically = **?** * If no neurologic recovery, surgeries like = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Repair of Severance**: * Requires ***surgical intervention*** * Prognosis typically ***poor*** * If no neurologic recovery, surgeries like ***tendon transfers*** may improve function.

# _ **?** _ neuropathy = * Involves two or more nerves in different parts of the body; individual nerves are affected, producing a random, asymmetrical presentation of signs. * Occurs when ***diabetes*** or ***vasculitis*** cause ischemia of the nerves. ## Footnote *Peripheral Nerves & Neuropathies*

**Multiple Mononeuropathy**: * Involves two or more nerves in different parts of the body; individual nerves are affected, producing a random, asymmetrical presentation of signs. * Occurs when diabetes or vasculitis (inflammation of blood vessels) cause ischemia of the nerves

***Multiple Mononeuropathy*** produces a random, _ **?** _ presentation of signs. ## Footnote *Peripheral Nerves & Neuropathies*

**Multiple Mononeuropathy**: * Involves two or more nerves in different parts of the body; individual nerves are affected, producing a ***random*** , ***asymmetrical*** presentation of signs.

# _ **?** _ neuropathy = Hallmark signs include symmetrical involvement of sensory, motor, and autonomic fibers, often progressing from ***distal to proximal*** . ## Footnote *Peripheral Nerves & Neuropathies*

**Polyneuropathy**: **-** Neuropathy involving multiple (poly) nerves in the body * Hallmark signs include ***symmetrical*** involvement of sensory, motor, and autonomic fibers, often progressing from ***distal to proximal*** . ## Footnote “ ***Distal symmetrical polyneuropathy*** ”

# Polyneuropathy * Symptoms typically begin in the (**hands** or **feet**) = **?** * ***Upper*** or ***Lower*** motor neuron = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Polyneuropathy**: **-** Symptoms typically begin in the ***feet*** and then appear in the hands and areas of the body supplied by the longest axons ( ***length-dependent*** ) * Stocking and glove pattern * Polyneuropathies are **NOT** the result of trauma. * Multiple variants, but we will focus on most common presentations. * ***Lower*** motor neuron

Stocking and glove pattern, makes you think **?** * (**a**) Traumatic myleinopathy * (**b**) Traumatic axonopathy * (**c**) Multiple mononeuropathy * (**d**) Polyneuropathy ## Footnote *Peripheral Nerves & Neuropathies*

* [Stocking and glove pattern](https://www.medicalnewstoday.com/articles/stocking-glove-neuropathy#what-it-is)*** , makes you think **?** * (a) Traumatic myleinopathy * (b) Traumatic axonopathy * (c) Multiple mononeuropathy * (**d**) **Polyneuropathy**

# What kind of neuropathy... A = **?** B = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Mononeuropathy** vs. **Polyneuropathy**: * **A** = Multiple Mononeuropathy * **B** = Polyneuropathy **Notes**: **-** Length-dependent **-** Terminals of longest nerves affected, therefore: * Distal symmetrical * Distally affected first * Motor loss, sensory loss, autonomic dysfunction

# Polyneuropathy Most common causes = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Polyneuropathy**: **-** Causes are **NOT** trauma, can be toxic, metabolic or autoimmune. **-** ***Most common causes*** include * Diabetes (diabetic neuropathy) * Nutritional deficiencies secondary to alcoholism * Autoimmune diseases (GBS). **-** A variety of therapeutic drugs (CIPN), industrial and agricultural toxins, and nutritional disorders can cause polyneuropathy

# Diabetic Polyneuropathy * Primary presenting factor = **?** * Can also lead to = **?** | *Can also lead to ... (what impairments)* ## Footnote *Peripheral Nerves & Neuropathies*

**Diabetic Polyneuropathy**: * Present in up to 90% of patients with DM * Pathogenesis not fully understood, although hyperglycemia felt to be involved. * Pain is ***primary presenting factor***, often worse at night, burning to tingling like pins and needles. * Presence of ***allodynia*** (pain response from non-painful stimulus). * Can also lead to somatosensory impairments, loss / impaired sensation, sores / blisters, delayed wound healing, loss of toe / foot (Loss of balance/ falls).

Hallmark is midfoot collapse with “rocker-bottom” foot = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**[Charcot Foot](https://my.clevelandclinic.org/health/diseases/15836-charcot-foot)**: * Interaction of multiple factors within DM polyneuropathy. * Hallmark is midfoot collapse with “rocker-bottom” foot. * High risk for breakdown, orthotics usually necessary.

Medications associated with the medical management of DM Polyneuropathy include = **?** ## Footnote *Peripheral Nerves & Neuropathies*

***Medical Management*** of DM Polyneuropathy: **-** Improve glycemic control **-** Treatment of pain challenging, and pain management judged effective if 50% reduction in pain **-** Medications: * ***Anticonvulsants*** : Analgesia and improved sleep. * ***Antidepressants*** : First line treatment. * ***Opioids*** : 2nd or 3rd line treatment * ***Topical agents*** : fewer side effects than medications and include capsaicin cream and lidocaine patches.

PT for DM Polyneuropathy should focus on = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**PT** for DM Polyneuropathy: **-** **Exercise**: Improve glycemic control, anti-depressive effects * Address balance/gait impairments from proprioception deficits. **-** **Address strength deficits**: according to prognosis and treatment goals * Consider whether patient deconditioned **-** **Orthoses** are frequently used to stabilize weight-bearing joints * Prevent sprains and strains. * Prevent dropping of the forefoot during gait in cases of paresis or paralysis of the tibialis anterior muscle * Prevent deformities from paresis, paralysis, and lack of sensation. **-** **Sensory deficits**

# DM Polyneuropathy Keys to foot care = **?** | *think shoes* ## Footnote *Peripheral Nerves & Neuropathies*

**Foot Care**: * Wash your feet with soap in warm, ***NOT*** hot, water, 90° - 95° F is safe, or your elbow to test the warmth of the water. * After washing and drying your feet, put talcum powder or cornstarch between your toes. **-** **Shoe Info**: * Wear shoes, that fit & protect your feet, and socks all the time. * **-** Walking shoes and athletic shoes are good for daily wear. * ***DO NOT*** wear vinyl or plastic shoes, because they do not stretch or “breathe.” * Buy shoes at the end of the day, when your feet are the largest, so that you can find the best fit.

# Alcoholic & Vitamin Deficiency Polyneuropathy * Primary Treatment = **?** * Secondary Treatment = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Alcoholic and Vitamin Deficiency Polyneuropathy**: * ***Primary Treatment*** : Abstain from alcohol, vitamin supplements, improve nutrition. * ***Secondary Treatment*** : Medications and therapy similar to DM polyneuropathy. **-** **Notes**: * Vitamin deficiencies include B1 (thiamine), B6, B12, folate, niacin, and vitamin E. * Nutrition usually poor * Symptoms similar to DM polyneuropathy

# _ **?** _ neuropathy = Can be caused by the neurotoxic effects of many cancer agents, and has symptoms similar to DM polyneuropathy. ## Footnote *Peripheral Nerves & Neuropathies*

**Chemotherapy Induced Polyneuropathy**: * Also called ***Chemo-induced peripheral neuropathy*** (CIPN). * Neurotoxic effects of many cancer agents. * Symptoms similar to DM polyneuropathy. * Treated medically similar to DM polyneuropathy.

# **?** Syndrome = * Involves acute inflammation and demyelination of peripheral sensory and motor fibers. * In 2/3 of cases it is preceded by an intestinal infection. * Symmetrical motor loss in legs, then in trunk and arms, motor involvement is more severe. * Absent/ diminished reflexes * In severe cases, respiratory involvement. ## Footnote *Peripheral Nerves & Neuropathies*

**Guillain-Barré [Syndrome](https://www.mayoclinic.org/diseases-conditions/guillain-barre-syndrome/symptoms-causes/syc-20362793)**: * Involves acute inflammation and demyelination of peripheral sensory and motor fibers. * Occurs 2-3 weeks after a mild infection. * In 2/3 of cases it is preceded by an intestinal infection that activates the immune system causing production of an antibody that mistakenly cross-reacts with the myelin sheath.

# Guillain-Barré Syndrome Diagnosis ## Footnote *Peripheral Nerves & Neuropathies*

*Guillain-Barré Syndrome* - **Diagnosis**: ## Footnote * Evaluation guides treatment, during the evaluation we should look for patterns. We (PT) should surround abnormality with normality.

* Dysfunction of peripheral nerves and the muscles they innervate can be evaluated by _ **?** _ . | BONUS = *What information does this give us* ? ## Footnote *Peripheral Nerves & Neuropathies*

**Electrodiagnostic Studies**: * Dysfunction of peripheral nerves and the muscles they innervate can be evaluated by ***electrodiagnostic studies***. * BONUS = Recording electrical activity from nerves and muscles by nerve conduction and EMG studies ***reveal the pathologic location & are often diagnostic***. * *Studies can be diagnostic as well as prognostic*

# Nerve Conduction Studies = **-** The application of external current and record response from large diameter, myelinated axons. * What does a segment with slow nerve conduction indicate = **?** * Three key parameters = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Nerve Conduction Studies** = The application of external current and record response from large diameter, myelinated axons. * Response depends upon site of stimulation and location of recording electrodes. * Slow nerve conduction ***across the site of damage*** w/ normal conduction in the axon segment proximal and distal to the injury. **-** ***Key parameters***: 1. ***Latency*** : Time from stimulus to response. 2. ***Velocity*** : Speed of conduction across segment. 3. ***Amplitude***

# Electromyography * What is it = **?** * What are these used to investigate = **?** * Two key parameters = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Electromyography**: * Insertion of recording electrode (needle) into muscle, view and listen to electrical activity of muscle. * Generally investigates ***axonal & muscular integrity***. **-** ***Key parameters*** : 1. Insertional and rest activity 2. Recruitment activity

In patients 50 y/o or older, the presence of two or three signs correlate highly with peripheral neuropathy. * What are the three signs = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**Clinical Testing**: **-** Presence of two or three signs correlate highly with electrodiagnostic evidence of peripheral neuropathy. * Absence of ankle jerk reflex * Impaired vibration * Impaired position sense of the great toe

# Distinguising Peripheral F/ Central Nervous System **-** ***Distribution of signs & symptoms*** : * PNS = **?** * CNS = **?** **-** ***Nerve conduction study*** : * PNS = **?** * CNS = **?** **-** ***Muscle tone*** : * PNS = **?** * CNS = **?** **-** ***Muscle atrophy*** : * PNS = **?** * CNS = **?** **-** ***Phasic stretch reflex*** : * PNS = **?** * CNS = **?** ## Footnote *Peripheral Nerves & Neuropathies*

**-** ***Distribution of signs & symptoms*** : * **PNS** = Peripheral nerve pattern * **CNS** = Dermatomal or myotomal pattern **-** ***Nerve conduction study*** : * **PNS** = Slowed or blocked conduction; decreased amplitude or recorded potentials * **CNS** = Normal **-** ***Muscle tone*** : * **PNS** = Lower motor neuron involvement; hypo-tonia * **CNS** = Upper motor neuron involvement; hyper-tonia **-** ***Muscle atrophy*** : * **PNS** = Rapid muscle atrophy indicates denervation * **CNS** = Muscle atrophy progresses slowly **-** ***Phasic stretch reflex*** : * **PNS** = Reduced or absent * **CNS** = Hyperactive or normal

Peripheral Nerves and Neuropathies Flashcards

(60 cards)