week 7 : neuromuscular disorders Flashcards
The nervous system : pathophysiology review :
is imposed of two divisions what are they ? and what undergoes them ?
1) CNS ( central nervous system ) -> brain, spinal cord, cranial nerves 1 and 2
2) PNS ( peripheral nervous system ) -> cranial nerves 3-12, spinal nerves, and autonomic system
what are the two types of cells of the nervous system
neurons and glial cells
what are neurons ?
primary functional unit of the nervous sytem
what are the 3 characteristics of the neurons
1) excitability
2) conductivity
3) ability to influence other cells
what is this description describing ( hint it’s a term ) : ability to generate or start an impulse
excitability
The ability to transmit : what term is this ?
conductivity
able to communicate to the other cells : in other words what is this characteristics out of the 3 when utilizing neurons
ability to influence other cells
what are the structures that may be affected by neuromuscular diseases?
cell body, the axon, and the dendrites of the neuron
Recall from physiology ( bruh i f ing forgot dont quote me ) : many axons are myelinated and what does myelin contribute ?
myelin is an insulating layer or sheath, that forms around neurons including those in the brain and spinal cord
Myelin or sheath allows what in terms of the neurons ( recall that it forms around the neurons including those in the brain and spinal cord )
myelin sheath allows electrical impulses to transmit quickly and efficiently along the nerve cells or along the neuron cells
what are one of the main function of the neuron?
nerve impulse
what is the function of the neuron ?
initiates, received, and process message that are coming both from within the body and externally
communication between neurons start with what ?
generation of an action potential
what does action potential rely on ?
sodium and potassium once the impulse has started it sets off a series of action potentials into play
Not a question, just remember***
Recall : action potential relies on electrolytes such as sodium and potassium Once the impulse has started it sets off a series of action potentials into play
When it reaches the end of the neuron it comes to the synapse or the gap between the two neurons and this is where neurotransmitters are released in order to continue the message across the synapse into the next neuron or into the next different body cell, and this process is going to be continued until the impulse reaches its intended destination.
name the characteristics that undergoes nerve impulse
neuron initiates, received, and process messages
begins with action potential
action potential - rapid, self propagating, and transient change in voltage across the cell membrane, causes by sodium influx and potassium efflux
after the impulse is initiated, it sets off a series of action potentials that travel along the axon
characteristics of the nerve impulse : at the end of the neuron, neurotransmitters are released that promote what ?
promote transmission across the synapse (junction between the nerve cells )
this continues until the impulse reaches its destination
what must a signal cross over in order to continue communication with the desired message ?
cross over the synapse
what is the usual final destination of a synapse?
something like a gland, endocrine , or a muscle such as smooth muscle or cardiac musc;e
what is this describing : structural and functional junction or ‘bridge’ between two neurons
synapse
this is how impulses travel until they reach their final destination which is a gland or muscle: what is this describing
synapse
what are the structures included in synapse
pre synaptic terminal
synaptic cleft
receptor site on post synaptic cell
Synapse:
________ are key in promoting the transition from one neuron to another
neurotransmitters
neurotransmitters is what type of agent ?
this is a chemical agent
true or false. Neurotransmitters can be excitatory or inhibitory
true
when the impulse from one neuron reaches the end of the axon right before the synapse, it releases a chemical substances called what ?
neurotransmitters
Describe the concept “ swim” of neurotransmitters in the notes
the neurotransmitters swims across the gap or synaptic cleft ( this is the space between the two neurons )
how does neurotransmitters attacthes to the receptors after it “ swims “
the neurotransmitters attaches to the receptors sites of the post synaptic neuron ( post synaptic neuron )
Recall that neurotransmitters can be excitatory : go more in depth of this
cause influx of sodium , promoting the firing of an action potential
Recall that neurotransmitter can be inhibitory : go more in depth with this concept
cause efflux of potassium, usually preventing the firing of an action potential
This stops the message from getting transmitted what type of neurotransmitter am i ?
inhibitory
what can block and enhance neurotransmitters ?
drugs and toxins
common neurotransmitters ( serves a foundation for mental health ) what are they ?
GABA
acetylcholine
dopamine
glutamate
norepinephrine
serotonin
match the following definitions with the terms listed below :
- controls movement and posture. regulates mood
- excitatory neurotransmitter associated with memory and learning
- important for attentiveness, sleeping, dreaming, and learning, also released as hormone and affects blood vessel constriction/increased heart rate
- regulates body temp, sleep, mood, appetite, and pain
- inhibitory neurotransmitter distributed in the neurons of cerebral cortex. contributes to motor control, vision, and regulates anxiety
- Excitatory neurotransmitter that triggers muscle contraction and stimulates secretion of hormones. Affects alertness, focus, anger, aggression, sexuality, and thirst
a. GABA
b. Glutamate
c. Dopamine
d. Acetylcholine
e. Norepinephrine
f. Serotonin
- c
- b
- e
- f
- a
- d
motor pathway is critical to the message being blocked, is this true or false.
false, critical to the message being received
In order for muscles to generate movement through the process of muscle contraction, this requires an impulse or message to be transmitted from the brain all the way down to that muscle through this series of events : what are they ?
- motor cortex ( upper motor neurons )
- spinal cord ( upper motor neurons )
- peripheral nerves ( lower motor neurons )
- neuromuscular junction
- muscle fibre
motor pathway starts in the brain within the motor cortex of the brain. true or false.
true
signals are passed on the upper motor neurons which travel through the spinal cord. is this true or false.
true
motor pathway : SATA
it reaches the peripheral nerves where they branch out and where those lower motor neurons take over and relay the message to the neuromuscular junction
Now this is the last point of contact or the last step in this motor pathway and then that impulse makes that final jump to the muscle fiber. Now if the message is relayed appropriately the muscle will contract and the desired movement is
generated.
all true
where does movement starts ?
starts in the brain
what is a motor cortex ?
responsible for goal orientated movements ( tasks ) , received information from other lobes of the brain
what is basal ganglia ?
located within the cerebrum, initiates and regulates body movments
what is cerebellum ?
regulates details of motor control, balance, smoothness, and coordination
this is important when we talk abt parkinson disease along with automatic ( such as swallowing, or remembering how to blink )
basal ganglia
this is near the centre of the brain , which allow brain to work together help over and coordinate muscle.
basal ganglia
this is at the back of your behind just above or behind spinal cord connect to the brain itself
posture ( so the body can move smoothly )
the action of grabbing ur spoon and bringing it to your mouth without spilling it
cerebellum
What is this describing : can approve or reject movement signals and this lets you control certain muscles without also using other muscles that are nearby
basal ganglia
what is this describing: a highway delivering messages from the brain to rest of body
spinal cord
what is this relating to:
Sends messages from the brain to peripheral nerves about what areas in the body need to move and how
* Receives messages from peripheral nerves about sensation and external stimuli, which is delivered to the brain
spinal cord
true or false regarding spinal cord: Each spinal segment contains a pair of nerve fibers (sensory and motor) that innervate a specific region of the body. These are called spinal nerves.
The spinal cord also has an ascending pathway that will deliver messages received from the body through sensation and it moves back up towards the brain.
ex. hand on stove
both true
what are sensory (afferent) and motor (efferent) nerves?
These nerves allow the brain to stay connected to the peripheral parts of the body so that our brain can receive and react to external stimuli information.
what is this describing: Nerves that branch out to muscles and organs all over the body (skin, muscles, viscera)
Connects the brain and spinal cord to all the areas of the body
spinla/peripheral nerves
true or false: Brain and spinal cord can send and receive information – allowing the body to react to environmental stimuli
tru
what are upper motor neurons?
Neurons of the brain and spinal cord that deal with movement
what is the end goal for motor/efferent nerves?
for the impulse to reach muscles, glands, and organs, depending on the required movement
what is descending tract ?
specific tracts (pathways) extending from the brain, to the spinal cord, and to the muscle. This is how the brain tells muscles to move.
different between upper and lower motor neurons
Upper Motor Neurons travel between the brain and spinal cord, they originate in the cerebral cortex and move down the spinal cord.
- Lower Motor Neurons travel from spinal cord to muscle, they originate in the spinal column, brainstem, and some cranial nerves. They are the link between upper motor neurons and muscles. The upper motor neuron “passes the baton” to the lower motor neuron who takes it to the muscle.
simply put: motor cortex of the brain - upper motor neurone (thru the spinal cord)- lower motor neurone - muscle
yesss
select all that apply regarding neuromuscular junction:
last step right before it reaches the muscle
Skeletal muscle does not require a nerve impulse to contract
Bridge between axon of the nerve cell and the adjacent muscle cell
* Neurotransmitters are released from the peripheral neuron (nerve cell) and diffuse across the neuromuscular junction to bind with receptors on the muscle fiber
* This triggers a muscle contraction
all true except skeletal muscle DOES require a nerve impulse to contract
what step requires a nerve impulse to contract?
neuromuscular junction
what is sensory/afferent nerves known as?
ascending tract
select all that is true regarding sensory/afferent nerves?
Afferent or sensory Neurons carry sensory information to higher levels of CNS from receptor sites in the skin, muscles, joints, viscera, and blood vessels. They tell the brain about pressure, vibration, position sense, body position, temperature, pain, body position (balance)
Nerve cells activated by sensory input from the
environment
* Sound, touch, heat, light, smell, taste (senses)
all true
what send messages to the nervous system about the information received
sensory/afferent nerves
quick summary - (just read)
Let’s say you’ve just returned from the gym and you’re about to take a shower. You
turn on the shower first and you check the temperature of the water with your
wrist. Your skin receptors will detect the temperature so that’s that external
stimulus.
The message will travel up the ascending pathway along those peripheral nerves to
the spinal cord, up the spinal cord to the cerebral cortex within the brain.
Here your brain will process the information and identify that the water is too
hot.
The next step is to coordinate a plan and initiate those movements.
So the cerebral cortex is again organized and has a plan of which message it is
going to send to the rest of the body. That message is then sent back down along
the descending pathway which starts in the brain in that cerebral cortex.
It travels to those upper motor neurons down the spinal cord and to the lower motor
neurons.
Finally crossing the neuromuscular junction to reach the muscles of the hand with
the help of those chemical neurotransmitters. Finally, the muscles of the hand
receive that message and contract to perform the function of switching the tap and
adjusting the water to a cooler temperature.
yayyyy ur ugg
what are the 12 cranial nerves and type of sensory ?
olfactory 1 - sensory
optic 2 - sensory
oculomotor 3 - mixed
trochlear 4 - motor
trigeminal 5 - mixed
abducens 6 - motor
facial 7- mixed
acoustic 8 - sensory
glossopharyngeal 9 - mixed
vagus 10 - mixed
spinal 11 - motor
hypoglossal 12 - motor
what are the four neuromuscular disorders for this lesson?
- MultipleSclerosis
- Parkinson’sDisease
- Peripheral neuropathy
- SpinalCordInjury
what is multiple sclerosis?
Chronic, inflammatory autoimmune disorder
attacks and destroys normal tissue
damages the myelin sheath affecting neurons of the brain spinal cord and optic nerve
what is this describing: Characterized by chronic inflammation, demyelination, and scarring in the CNS
MS - multiple sclerosis
what are the risk factors of multiple sclerosis?
females, colder climates (vitamin D deficiency), average age of onset (30 years old), inherited (there is a genetic link) also obesity, smoking
what are the precipitating factors?
infection, trauma, pregnancy, stress, fatigue, poor health, surgery
true or false: MS can affect both motor and sensory neurons along ascending and descending pathways, so this can result in difficulty with muscle movements, muscle strength and sensation due to neurons not communicating properly both ways.
true
what are the clinical manifestations of Ms (there are sooo many but added one from each system)
resp: diminished cough reflex
urinary: hesitancy
GI: dysphagia
musculoskeletal: fatigue, muscular atrophy, slurred speech
neuro: apathy, emotional lability
sensory: blurred vision
reproductive: loss of genital sensation
is Parkinson’s autoimmune?
no!!!
what is Parkinson’s?
Progressive, neurodegenerative disease of the central nervous system
what is the average age of diagnosis? what gender is it more common in
60, men
what are the risk factors for Parkinson’s?
Other risk factors include; antipsychotic medications, illicit drug use, dementia, exposure to a variety of chemicals
select all that is true about Parkinson’s:
Proper brain function relies on a delicate balance between the neurotransmitters Dopamine (inhibitory) and Acetylcholine (excitatory).
In PD, dopamine producing neurons in the substantia nigra, and midbrain are destroyed.
Leads to an imbalance – dopamine is required for normal functioning of the extrapyramidal motor system
true
what is extrapyramidal motor system responsible for?
automatic - involuntary contractions (blinking, swallowing)
true or false: In Parkinson’s the neurons that produce dopamine that are within the midbrain and the substantia nigra are destroyed and this leads to an imbalance between dopamine and acetylcholine.
true
true or false: when we have a shortage of dopamine, we see the loss of the ability to refine those voluntary movements as well as symptoms related to the loss or dysfunction of those extra pyramidal automatic functions. The balance between excitatory acetylcholine producing neurons remain active and the resulting excessive excitation of neurons prevents a person from controlling or initiating voluntary movements.
true
what are the clinical manifestations of Parkinson’s?
tremors - more obvious at rest - pill rolling motion
rigidity - increased resistance to passive motion, jerky intermittent catches and movement
bradykinesia
are these findings true in person with Parkinson’s: blank facial expression, forward tilt to posture, tremor, slow monotonous slurred speech, tremor, short shuffling gait
true
how many stages of Parkinson’s are there?
5 stages
what are the 5 stages of Parkinson’s?
Stage I – Initial Stage
* Unilateral limb movement; minimal weakness; hand and arm trembling
* Stage II – Mild Stage
* Bilateral limb involvement; mask-like face; slow, shuffling gait
* Stage III – Moderate Disease
* Postural instability; increased gait disturbances
* Stage IV – Severe Disability * Akinesia; rigidity
* Stage V – Complete ADL Dependence
what are some complications of neuromuscular disorders?
Aspiration
Pneumonia
Urinary tract infections
Pressure sores
Malnourishment
Falls
anatomy of the spinal cord - REVIEW!!!
white matter (sensory and motor fibers ascending and descending tract)
grey matter, dorsal root, dorsal horn, ventral horn and ventral root, spinal nerves etc
where does spinal cord ext through
foramen magnum
true of false regarding spinal cord: Contains a pair of dorsal (afferent) sensory nerve fibers
* Contains a pair of ventral (efferent) motor nerve fibers
* Each pair of nerve fibers innervate specific regions of the neck, trunk and limbs
all true
true or false regarding spinal cord: he combined motor/sensory nerve system is called spinal nerves
* Voluntary motor system cells located in anterior horn of spinal cord grey matter
* Involuntary motor system cells are in anterolateral portion of spinal cord grey matter
true
true or false: Sensory fibers are in dorsal root ganglia
true
what are the neurons and tracts in the spinal cord?
Ascending Tracts
* Descending Tracts
* Upper Motor Neurons
* Lower Motor Neurons
true or false: Sensory fibers are in ventral root ganglia * As sensory and motor nerves exit the spinal column, they
extend to the peripheral structures (skin, muscles, organs)
first one false - its dorsal root ganglia
review of the spinal cord a and p: pain receptor in finger - sensory neurone carries nerve impulse to the spinal cord - connecting (relay) neurone caries impulse from the sensory to the motor neurone - motor neurone carries impulses from the spinal card to the muscle - biceps muscle bends arm
true
what are dermatomes ?
area of skin innervated by sensory fibers of a dorsal route
what is this describing: Indicate general pattern of sensory innovation by spinal segments
dermatomes
true or false regarding myotomes: muscle group innervated by sensory neurons of a ventral route
FALSE its motor u sucked innnnn
just some info to look over:
Dermatomes and myotomes become very important in our assessments and based on the deficit, it can help us determine what level of the spinal cord is involved with a
spinal cord injury and vice versa. From the level of the spinal cord injury, we can
anticipate what deficits the person may experience as a result of their injury.
yasssss
select all that is true regarding vertebral column:
* Protects the spinal cord
* Supports head
* Provides flexibility
true
how many vertebrae are there/ go more in depth
Each vertebrae has a central opening through which spinal cord passes
33 individual vertebrae
7 cervical
12 thoracic
5 lumbar
5 sacral
4 coccygeal
what is the order of the vertebrae column?
cervical, thoracic, lumbar, sacral, coccygeal
what are some common causes of spinal cord injury?
motor vehicle collisions, motorcycle crashes, and falls
what is this describing: Disruption in neuronal tissue within spinal canal as a result of trauma, disease, or degeneration
spinal cord injury (SCI)
what is tetraplegia? what about paraplegia?
Tetraplegia - paralysis and loss of sensation of both arms, legs, and trunk, occurs with damage at C8 and above
Paraplegia - paralysis and loss of sensation of both legs and trunk, occurs with damage at T1-T6
above C4 indicates?
total loss of respiratory muscle function
above t6 indicates?
Cardiovascular changes (bradycardia/hypotenstion)
true or false regarding level of injury: Skeletal level of injury is the vertebral level where damage to bones and ligaments is most extensive
Neurological level of injury is the lowest segment of spinal cord at which both sensory and motor function are normal bilaterally
true
what systems are affected by the clini mani of spinal cord injury ? and possibly what could happen
DVT could happen
respiratory system is affected along with gi system and urinary system and cardiovascular system
true or false. The higher the injury the more serious the deficits become because its closer to the brain, is this true ?
yes this is true
below the c4 level we have what type of nerve ? and what does this nerve do ?
we have the phrenic nerve, to innervate the diaphragm, for expiration an inspiration
true or false. an individual who has a spinal cord injury could experience what type of clini mani ? ** hint this is term that describes the inability to maintain to ambient temp. ( cannot regulate, just matches the room temp)
polycothermia
what is polycothermia ?
inability to maintain to ambient temperatures
cannot regulate ( just matches the room temp. )
they do not have the ability to sweat or shiver because the signals to the hypothalamus is blocked
during a spinal cord injury :
C5 or C6 - can still breathe on their own but vulnerable for conditions,
but what type of conditions are they vulnerable for ?
when spinal cord injury affects the lowest cervial or throacic level, what happens here ?
of allectasis or pneumonia ( hard time breathing stilll )
innervates the abdominal or intercostal muscle
( recall : these are accessory muscle for WOB or force coughing ( to clear out sputum ) further risk for pneumonia and allectasis
during a spinal cord injury we are aware that gi system is impacted, what is the hypomotility and neurogenic bowel ?
hypomotility - bowels are not properly moving ( paralytic ileus )
development of neurogenic bowel - fecal incontinent
what is this describing : damage through destruction or inflammation
peripheral neurophathy
what are the causes of peripheral neuropathy
diabetes
hypothyroidism
vitamin deficiencies
MS
what type of pain do peripheral neuropathy experience ?
neuropathic pain ( pathologic )
What type of processing does peripheral neuropathy undergo ?
abnormal processing of the sensory and motor nerves input as a result of damage
what type of nerves can peripheral neuropathy affect ?
Can affect single nerve distribution (mononeuropathy) or can affect multiple nerves (systemic origin – polyneuropathy)
how will clini mani occur during peripheral nueropathy?
Clinical manifestations will follow the dermatomes and myotomes of the affected nerve
This is different from nociceptive pain, doesn’t need to necessarily be tissue damage or a pain producing stimuli in order to feel that pain sensation: what situation is this describing ?
peripheral neuropathy
recall that : * Diabetes
* Hypothyroidism
* Vitamin Deficiencies
* MS
can cause peripheral neuropathy
explain the concepts further
diabetes- complex mechanism through changes in metabolic dysfunction, inflammation , ischemia, which overall can lead to that damage of that nerves
Hypothyrodism
Vitamin deficienciences- vitamin B12. : patient who is vegan and not consuming a lot of animal products. So in patients like this we want to make sure that they’re getting that B12 through additional supplementation to their diet.
MS- damage to the myelin sheath this can affect the way that our peripheral nerves function.
hiv is another example cause of peripheral neuropathy, as is HIV
whats another disease that can cause peripheral neuropathy ?
Lime disease is another cause for peripheral neuropathy. So if we have a patient who’s experiencing this peripheral neuropathy of an unknown cause, it’s a good idea to make sure that we test them for Lyme disease
peripheral neuropathy : clinical manifestations
what undergoes sensory dysfunction?
- Poorly localized
- Shooting ,burning ,fiery
- Shock-like, tingling, painful,
- Numbness
- Extreme sensitivity to touch * Weakness, paraesthesia
PERIPHERAL NEUROPATHY: CLINICAL MANIFES TATIONS: what undergoes autonomic dysfunction
bowel, bladder, digestive dysfunction
heat intolerance
hypotension
