CNS tx class 1 Flashcards
CNS consists of
brain and spinal cord
(brainstem / spinal cord)
brainstem consists of
midbrain,
pons,
medulla oblongata
Peripheral nervous system consists of
autonomic ns
enteric ns
somatic ns
divisions of autonomic nervous system
sympathetic ns
parasympathetic ns
autonomic nervous system description
involuntary,
sensory from visceral organs,
motor to smooth muscles/ cardiac muscles & glands
description of enteric ns
involuntary,
sensory from chemical changes in the GI tract & stretch,
motor to smooth muscles
description of somatic ns
consciously controlled & voluntary,
sensory receptors & motor neurons to skeletal muscles
spinal cord runs through the ___
spinal canal
spinal cord connects to brain via the ____
brainstem
the brainstem is the originating point of which structures ?
(mostly)
CRANIAL nerves
Actually – MOSTLY from brainstem
a few exit from cerebrum
the spinal cord is the originating point of which structures ?
Nerve roots
the spinal cord relays information between which two structures?
the BRAIN
and the PERIPHERAL NERVES
why is the CNS important?
what does it do?
Controls most body functions including awareness, movements, thoughts, speech and memory
midbrain is AKA
mesencephalon
mesos = middle
encephalon = brain
diencephalon etymology
di = across
encephalon = brain
from top to bottom
diencephalon
(BRAINSTEM)
mesencephalon
pons
medulla oblongata
spinal cord
where is the cerebellum located?
POSTERIOR to brainstem (midbrain, pons, medulla)
where is the diencephalon located?
superior to brainstem (right above midbrain)
diencephalon components
thalamus
hypothalamus
epithalamus
what is the cerebrum?
where does it sit?
cerebrum is the largest part of the brain
sits on the DIENCEPHALON
cranial nerves
1 olfactory
2 optic
3 oculomotor
4 trochlear
5 trigeminal
6 abducens
7 facial
8 vestibulocochlear
9 glossopharyngeal
10 vagus
11 accessory
12 hypoglossal
motor pathways are defined as …
The neural circuits or pathways in the nervous system
Responsible for transmitting signals from the brain to the muscles,
leading to voluntary muscle movements
coordinate and control muscle contractions
TWO primary motor pathways
corticospinal (PYRAMIDAL) pathway
extrapyramidal pathway
CORTICOSPINAL PATHWAY origin
primary motor cortex
(in cerebrum – cerebral cortex)
corticospinal pathway starts out as ____
upper motor neurons – from the cerebral cortex
where do the UMNs of CORTICOSPINAL pathway travel through/to from the cerebral cortex?
travel via INTERNAL CAPSULE
to BRAINSTEM
& SPINAL CORD
the UMNs synapse with LMNs in SPINAL CORD
LMNs transmit signal to mm (voluntary mvmt)
internal capsule of brain
The internal capsule is a paired white matter structure, as a two-way tract, carrying ascending and descending fibers, to and from the cerebral cortex
EXTRAPYRAMIDAL PATHWAY – origin
involves multiple subcortical nuclei
(brain regions outside the primary motor cortex)
function of EXTRAPYRAMIDAL pathway
coordinating and regulating muscle tone, posture, and involuntary movements
(involuntary movement
e.g. REFLEXES/speech)
the corticospinal pathway DIRECTLY runs between the spinal cord and the ____
primary motor cortex
the extrapyramidal pathway on the other hand …
extrapyramidal pathway involves more complex and indirect connections
in the corticospinal tract, UMNs originate ____
Originate in the primary motor cortex of the cerebral cortex
Travel through the internal capsule, brainstem (particularly the medulla), and spinal cord
LMNs
Located in the spinal cord.
Receive signals from the upper motor neurons.
Extend their axons out of the spinal cord to innervate skeletal muscles.
how do mm contractions occur in the context of UMN/LMN
When the LMN receive signals from the UMN, they transmit electrical impulses to the skeletal muscles.
This results in the contraction of the targeted muscles, leading to voluntary movements.
damage/disruption to motor neuron pathways can lead to
motor deficits, such as weakness, paralysis, or impaired coordination
spinal nerves from CERVICAL SPINE region
signals to & from
—> head, neck, shoulders, arms & hands
spinal nerves from THORACIC SPINE region
signals to & from
—> part of the arms
—> & the anterior & posterior chest & abdominal areas
spinal nerves from LUMBAR SPINE region
—> legs & feet,
—> some pelvic organs
spinal nerves from SACRAL SPINE region
—> lower back & glutes,
—> pelvic organs & genital areas,
—> some areas in the legs & feet
COCCYGEAL SPINAL NERVE
located at the bottom of the spinal cord
“part of the coccygeal plexus, which supplies the coccyx, the sacrococcygeal joint, and the skin over the coccyx.”
dermatomes
An area of skin supplied by sensory fibers from a single spinal nerve.
These nerves transmit sensory information (such as pain, temperature, and touch) from specific areas of the skin to the spinal cord and then to the brain.
Typically organized in a segmented pattern corresponding to the spinal nerves.
Myotomes
A group of muscles primarily innervated by the motor fibers of a single spinal nerve.
Motor neurons in the spinal cord send signals to specific muscles through these myotomes, enabling voluntary muscle movement.
Also organized in a pattern corresponding to specific spinal nerves.
c1/c2 myotome
neck flexion/extension
(MAGEE ONLY MENTIONS FLEXION)
c3 myotome
neck lateral flexion
c4 myotome
shoulder elevation
c5 myotome
shoulder abd
c6 myotome
elbow flexion/ wrist extension
c7 myotome
elbow extension/ wrist flexion
c8 myotome
thumb extension/finger flexion (???)
MAGEE SAYS THUMB EXTENSION AND/OR ULNAR DEVIATION
t1 myotome
finger abduction
MAGEE SAYS finger abduction and/or adduction
l2 myotome
hip flexion
l3 myotome
knee ext
l4 myotome
ankle dorsiflexion
l5 myotome
big toe extension
s1 myotome
ankle plantar flexion / hip extension
(& ankle eversion)
s2 myotome
knee flexion
Deep tendon reflexes – function
Quickly confirm the integrity of the spinal cord
Differentiate between UMNL vs LMNL
UMNL vs LMNL
if UMN affected = increase reflexes (non-basal ganglia disorders/ any area above anterior horn cells)
if LMN affected = decreased reflexes (anterior horn cells/ spinal roots/ peripheral nerves)
what are you looking for during DTR test?
Asymmetry: test the opposite side immediately after
Threshold for stimulus: how hard? Does it elicit the same response?
hyperactive DTR
Hyperactive = CNS lesions - test for weakness, spasticity
(UMNL?)
hypoactive DTR
Hypoactive = PNS, spinal roots, plexus - check for weakness, atrophy, fasciculations
(LMNL?)
c5 DTR
biceps brachii
c6 DTR
brachioradialis
c7 DTR
triceps brachii
l4 DTR
quadriceps (patellar tendon)
s1 DTR
gastroc/soleus (achilles)
DTR grading
0 = absent
1+ = trace
2+ = normal
3+ = brisk
4+ = very brisk (no sustained clonus)
5+ = sustained clonus
clonus define
“muscular spasm involving repeated, often rhythmic, contractions.”
etymology:
klonos = turmoil
SENSORY TESTING (assessments)
(PATIENT CLOSES EYES)
1) Touch perception - light vs deep
2) Temperature perception - hot vs cold
3) Pain perception
4) Two-point discrimination
5) Proprioception test
(e.g. finger to nose with eyes closed)
6) Vibration sense with a tuning fork
sensory tests / assessments should be done ____
Comparisons should be made from one side to the other & from proximal to distal of each extremity
(bilateral & proximal to distal)
MMT
baseline for Rx, Dx an injury, set up a rehab program
…?
break test
with gravity, gravity eliminated (plane parallel with gravity), gravity assisted (gravity used to help assist movement, eccentric contractions
“called the break test because when a therapist provides resistance the objective for the patient is to not allow the therapist to “break” the muscle hold.”
MMT grades
0 = no contraction detected
1 (trace) = trace (contraction seen/palpated, but no movement)
2 (poor) = moving though the full range with gravity eliminated
(THEREX says gravity REDUCED)
AAROM
3 (fair) = prime movers can actively move against gravity only, AROM
4 (good) = “prime mover is able to maintain average resistance throughout normal range but yields to break test.”
(THEREX)
5 (normal) = “prime mover demonstrates the ability to maintain average resistance through-out its’ normal ROM and is able to maintain a maximal isometric resistance at a particular point in its strength curve for at least five seconds (break test).”
(THEREX)
UMNL location
UMN lesions occur within the central nervous system (CNS), specifically within the brain or spinal cord
UMNL effect on mm tone
UMN lesions lead to increased muscle tone, a condition called hypertonia. This results in stiffness and resistance to passive movement.
UMNL vs reflexes
Hyperactive reflexes are often present due to disrupted inhibitory signals from the brain. Reflexes can be exaggerated or abnormal.
UMNL vs SPASTICITY
Spasticity, characterized by sudden muscle contractions or spasms, is a common feature of UMN lesions.
UMNL vs weakness/paralysis ?
Weakness or paralysis can occur due to disruption of signals between the brain and muscles. Muscles may not receive appropriate signals for coordinated movement.
EXAMPLES OF CONDITIONS WHERE UMNLs can occur
1) Stroke,
2) traumatic brain injury,
3) multiple sclerosis,
4) cerebral palsy,
5) and certain spinal cord injuries
LMNL location
LMN lesions occur outside the central nervous system, specifically within the peripheral nervous system (PNS), which includes the nerves that extend from the spinal cord to the muscles.
LMNL effect on mm tone
LMN lesions lead to decreased muscle tone, a condition called hypotonia.
This results in muscles feeling floppy and lacking resistance to passive movement.
LMNL vs reflexes
Reflexes are typically reduced or absent due to the interruption of signals between the spinal cord and muscles.
LMNL and atrophy
Muscles may show signs of atrophy (wasting) due to the lack of neural input.
LMNL vs weakness/paralysis
Severe muscle weakness or paralysis can occur due to the disruption of signals reaching the muscles directly.
EXAMPLES OF CONDITIONS WHERE LMNLs can occur
1) ALS (amyotrophic lateral sclerosis)
2) spinal muscular atrophy (SMA),
3) peripheral nerve injuries,
4) and certain types of neuropathy
note again the differences between UMNL & LMNL
The location of the lesion is the key distinguishing factor between UMN and LMN lesions.
UMN lesions involve damage within the CNS, while LMN lesions involve damage within the PNS.
can UMNL also lead to mm weakness?
YES
Both types of lesions can lead to muscle weakness and impaired movement, but the patterns of weakness and other symptoms are different.
however, UMNLs often result in ____
wheres LMNLs often result in ____
UMN lesions often result in increased muscle tone, hyperactive reflexes, and spasticity,
LMN lesions typically result in decreased muscle tone and reduced or absent reflexes.
conditions of UMNL vs LMNL
The conditions that cause UMN and LMN lesions vary, with different underlying causes and mechanisms.
SPASTICITY vs RIGIDITY (neurological SSx)
…
spasticity
resistance of a limb to PASSIVE MOVEMENT, abnormal increase of mm tone or stiffness of a muscle.
Due to damage of UMN
rigidity
resistance throughout ROM & even at rest
Due to over firing of UMN
spasticity generally only observed during ___
generally only during mm stretch (ie. not @ rest) usually accompanied with increase tendon reflexes
spasticity vs velocity of movement
Velocity depending - meaning more noticeable with fast movements
spasticity vs direction
Difference in resistance from one direction to another
spasticity is seen in which motor pathway?
PYRAMIDAL TRACT (corticospinal pathway)
EXAMPLES of conditions that can cause SPASTICITY
SCI
MS
CP
stroke
TBI
ALS
etc.
rigidity is seen during movement but also during ____
mm tone is increased even @ rest, present during PROM in all directions across individual joints
rigidity vs synergy
Absence of synergy
agonists and antagonists simultaneously contract
rigidity vs direction
all directions
rigidity is seen in which motor pathways?
Seen in EXTRAPYRAMIDAL pathway lesions
(E.g. rubiospinal or vestibulospinal tracts)
TWO types of rigidity
COGWHEEL RIGIDITY: hypertonic state w/ ratchet-like jerkiness
LEAD PIPE RIGIDITY: hypertonic state throughout ROM, simultaneous co-contraction of agonist & antagonist
EXAMPLES of conditions that can cause RIGIDITY
Parkinson’s
Huntington’s
general SSx of neurological conditions
…
flaccidity
Flaccidity: aka hypotonicity - decrease or loss of normal mm tone due to deterioration of LMN
Weakness, contractures, postural imbalances
..
tremors
Resting tremors,
intention tremors (initiated with movement)
altered gait
eg: circumduction gait in hemiplegia or MS
& bradykinesic or festinating gait seen in Parkinson‘s
ulcers
Decreased tissue health & edema leading to decubitus ulcers
seizures / speech dysfunction
..
bladder/bowel
Bowel & bladder dysfunction
psychological / psychosocial
Pain, behaviour & emotional changes
sensory dysfunction
Sensory & autonomic dysfunction:
Paresthesia or dysesthesia,
increase as sweated or secretions,
general abnormalities in temperature regulation
compensatory changes
mm hypertonicity,
fascia restrictions,
tendinitis,
overuse syndromes
autonomic dyreflexia (SCI)
Autonomic dysreflexia (AD) is a dangerous syndrome involving an overreaction of your autonomic nervous system
“It causes a sudden and severe rise in blood pressure, in addition to other symptoms. People who’ve had a spinal cord injury are most at risk.”
“reaction may include –> Change in heart rate. Excessive sweating.”
dysphasia vs dysarthria
“Dysarthria is a disorder of speech, while dysphasia is a disorder of language.”
“Dysarthria affects the muscles used to produce speech and can cause slow or slurred speech that is hard to understand. It differs from aphasia and dysphasia in that this disruption to speech is not a result of language selection or processing but rather articulation and pronunciation.”
aphasia vs dysphasia
same condition – differ in severity
(class notes may be incorrect b/c they don’t point this out)
important definitions
Dysarthria – defective speech due to muscular dysfunction, mental function is intact
Dyskinesia – a defect in the ability to perform voluntary movement
Dysmnesia – any impairment in memory
Dysphagia – inability to swallow
Dysphasia – impairment of speech resulting from brain lesion
Dyspnea – laboured difficult breathing
Dyspraxia – a disturbance in control and execution of voluntary movement
Dystonia – prolonged muscle contraction that causes twisting and repetitive movement or abnormal posture
Dysesthesia – abnormal sensation on the skin
Ataxia – defective muscular coordination
Paresthesia – sensation of numbness, prickling, tingling
Dysreflexia – individual with T6 or higher spinal cord injury experiences a life threatening uninhibited sympathetic response of the nervous system to a noxious stimulus
Aphasia – inability to speak; may be due to lack of comprehension of words as opposed to dysphasia (dysarthria???) (inability to coordinate muscles of speech)
Paralysis – temporary or permanent loss of function especially loss of sensation and voluntary control. Can be spastic (upper motor neuron) or flaccid (lower motor neuron)
developmental reflexes
..
what is a reflex
Involuntary, or automatic, action that the body does in response to a stimulus, without awareness.
neonatal reflexes (primitive reflexes)
Neonatal reflexes or primitive reflexes are the inborn behavioral patterns that develop during uterine life
what happens to (MOST) neonatal reflexes as baby grows?
They should be fully present at birth and gradually inhibited by higher centers of the brain as the infant grows and develops
three types of developmental reflexes
General body reflexes
Facial reflexes
Oral reflexes
Oral reflexes
Rooting ( 3-4 months )
Sucking
Gag (permanent)
Swallowing reflex
facial reflexes
Blink reflex (permanent)
Auditory orienting reflex (permanent)
general body reflexes
Moro / Startle reflex (integrated 2-4 months)
Palmar / plantar grasp reflex (integrated 5-6 months)
Walking / Stepping reflex (2-4 months)
Asymmetric tonic neck reflex (6 months)
Symmetric tonic neck reflex (9-11 months)
Babinski’s Reflex (8-12 months)
clinical significance of developmental reflexes
Developmental reflexes are automatic responses that are measured in terms of timing, strength, and symmetry and indicate how the signals are sent from the brain to the spinal cord and outward to individual muscles of the face, neck, torso, and extremities that are involved in postural control and movement.
what happens if developmental reflexes are retained?
Developmental reflex’s are retained with some learning disorders, ADHD, autism spectrum
____
Startle/Moro reflex (leading to issues with balance and coordination)
Asymmetrical tonic neck reflex (leading to head control and balance issues)
Symmetrical tonic neck reflex (leading to poor posture and hand-eye coordination issues)
Palmar Grasp reflex (leading to issues with fine motor skills)
Babinski reflex (leading to poor muscle tone, fatigue, vestibular related problems)
Rooting reflex (leading to issues with feeding)
