Week 5: Motor Impairments Flashcards
Define sign vs. symptom:
sign is objective and symptom is subjective
a positive sign is an indication that:
there is a presence of an abnormal behavior
a negative sign indicates a:
absence of normal behavior
A primary impairment is:
a direct effect of the pathology or lesion
a secondary impairment develops as:
a result of the original problem
Upper motor neuron lesions effect the:
motor cortex
descending motor tracts
brainstem
spinal cord proximal to alpha motor neurons
lower motor neurons effect:
alpha motor neurons ventral root motor nerve plexus peripheral motor nerve neuromuscular junctions
What sign do we see with upper motor neurons?
weakness, increased reflexes and increased tone
no effects on atrophy or fasciculations
what signs do we see with lower motor neurons?
weakness, atrophy, fasciculations, decreased reflexes and decreased tone
With a stroke, what signs will we see?
weakness, hypertonicity and hyperreflexia
with a brachial plexus injury, what signs do we see?
weakness, atrophy, fasciculations, decreased tone and decreased reflex
Neural contributions to strength reflect:
# of motor units recruited type of motor units recruited discharge frequency
musculoskeletal contributions to strength reflect:
length/tension relationship length of movement arm of the muscle cross sectional area available type of muscle fiber muscle fiber arrangement
What is weakness in the context of neuropathy?
inability to generate force or inability to correctly recruit or modulate motor neurons
muscle weakness leads to:
loss of movement and loss of power
lack of muscle activity and immobility
neurologically induced weakness may result from:
cortical lesion descending pathway injury peripheral nerve injury synaptic dysfunction at neuromuscular jxn muscle tissue damage
extent and distribution of weakness depend on:
extent and location of lesion
paralysis or plegia is:
total or profound loss of muscle activity
paresis is:
mild or partial loss of muscle activity
what are the 4 categories of distribution?
tetraplegia
monoplegia
hemiplegia
paraplegia/ diplegia
Impaired motor control is often worse with:
stress, distraction, fatigue
Motor recruitment is:
agonist activation + reflexive inhibition of antagonist
What are synergies?
Muscle and joint movements that occur in stereotypical patterns
synergies are the loss of:
single joint, isolated movement patterns
What is the upper extremity flexor synergy?
scapula retraction and elevation shoulder abduction and ER elbow flexion supination wrist finger flexion
What is the extension synergy in the lower extremity?
Hip extension, adduction and internal rotation
knee extension
ankle plantar flexion and inversion
toe plantar flexion
What are the myotomes we are responsible for knowing (C5 - T1) and (L1 - S1)
C5 - shoulder ABD C6: elbow flexion and wrist extension C7: elbow extension and wrist flexion C8: finger flexion and thumb extension T1: finger adduction L1 - L2: hip flexion L3: knee extension L4: ankle dorsiflexion L5: great toe extension S1: plantar flexion S2: Knee flexion
When we look at myotomes, our patient should be _________ and __________ movements should be observed
seated; isolated
stretch reflex dysfunction is damage to:
supraspinal structures involved in reflex modulation such as
——–the cerebellum and the corticospinal tract, reticulospinal tract, rubrospinal tract, —- ——–vestibulospinal tracts
spinal cord (interneurons and motor neurons)
sensory feedback systems
hyporeflexia (or areflexia) is a __________ motor neuron injury
lower
hyperreflexia is a ___________ motor neuron injury
upper
What neuroanatomical structures are involved with hyporeflexia?
alpha motor neuron and sensory neuron
what neuroanatomical structures are involved in hyperreflexia?
supraspinal structures and spinal cord structures
What deep tendon reflexes are we responsible for knowing?
(C5 - C7), L4 and S1
C5 - biceps C6 - brachioradialis C7 - triceps L4 - patella (quadriceps) S1 - Achilles (gastrocsoleus complex)
What are the deep tendon reflex grades?
0: absent 1+ hyporeflexia 2: normal 3+ hyperreflexia 4+ hyperreflexia with nonsustained clonus 5+ hyperreflexia with sustained clonus
A positive babinski’s test is characterized by:
fanning or extension of the toes to a stimulus
Tone is characterized by:
a muscle’s resistance to passive stretch
tone represents a state of:
slight residual contraction in normally innervated resting muscle (steady-state contraction)
What are contributions to normal tone influenced by?
physical inertia
intrinsic mechanical elastic reflex
spinal reflex muscle contraction or tonic stretch reflex
the spinal reflex muscle contraction consists of:
a net balance of descending input on motor neurons from corticospinal, rubrospinal, reticulospinal, and vestibulospinal tracts
cerebellar input
hypotonicity is characterized by:
reduction in passive resistance to lengthening
floppy - collapse into gravity, harder to excite
flaccidity - complete loss of muscle tone
hypotonicity is caused by
- afferent input from:
- lack of _____________ efference influence
- decreased input to:
stretch reflex
cerebellar
gamma motor neurons
what are the common pathologies that can cause hypotonicity?
- cerebellar lesions, down syndrome, late-stage ALS, muscular dystrophies, and post-polio
- acute CNS injuries that can progress to hypertonicity/spasticity once subacute or chronic
- can see with PNS injuries and connective tissue disorders
What is speed dependent?
spasticity
what is resistant to movement and independent of movement velocity?
rigidity
Spasticity occurs as a result of damage to:
descending pyramidal tracts
causes a loss of inhibitory effect on tonic stretch reflex and results in alterations to the threshold of reflex
spasticity CAN be associated with ___________, a condition that is more common in distal extremities than proximal
clonus
clonus and spasticity are characterized as a ___________ and oscillating stretch reflex.
rhythmic
What is commonly seen with basal ganglia dysfunction?
rigidity
rigidity is more commonly seen in our __________
flexors
Define the phrases that are associated with rigidity:
Lead pipe
cogwheel
clasp - knife
lead pipe = constant resistance to movement throughout the entire ROM
cogwheel = alternating episodes of resistance and relaxation
clasp knife = initial rigidity with sudden absence throughout the remainder of range
What kind of posturing will we see when there is a brainstem lesion above the red nucleus? Describe what that posturing looks like.
decorticate; UE flexion, LE extension/ IR/ and PF
What kind of posturing will we see when there is a brainstem lesion below the red nucleus? Describe what that posturing looks like.
decerebrate: UE and LE extension
What are functional implications associated with someone who has high tone?
abnormal posturing
misalignment
high risk of injury during prolonged sitting (skin breakdown)
bias with recruitment and increased likelihood of synergistic movement
destabilization with changes in position
What are the functional implications associated with someone who has a lower tone?
fall into gravity
high risk of injury associated during dynamic tasks
Tone assessment in UE consists of what motions at the shoulder, elbow, wrist, and hand?
shoulder - flex/ext. and IR/ER
elbow - Pronation/supination and flexion/extension
wrist - flex/extension
fingers - flex/extension
Tone assessment in LE consists of what motions at the hip, knee, ankle, and foot?
hip - abd/add. and flex/exten. and IR/ER
knee - flexion and ext.
ankle - DF and PF
foot - toe flex. and extension
What test measures spasticity and spasticity alone?
modified ashworth scale
Describe what happens at V1, V2, and V3 on the Tardieu scale.
V1 - slow as possible - PROM assessment
V2 - speed of limb falling under gravity - Spasticity assessment
V3 - fast as possible - spasticity assesment
Dystonia is seen when there is damage to:
the basal ganglia
A syndrome dominated by sustained muscle contractions that causes twisting, repetitive movements, and abnormal postures is called:
dystonia
What are the 5 characteristics of dystonia?
- damage to the basal ganglia
- syndrome dominated by sustained muscle contractions
- causes twisting, repetitive movements, and abnormal postures
- coactivation of agonist and antagonist
- focal, segmental, hemibody or generalized/ whole
rhythmic, involuntary oscillatory movements of a body part are called:
tremors
What are resting tremors?
occurs in the body part that is not voluntarily activated, relaxed
what are action tremors?
tremors produced by voluntary contraction of a muscle
Name and describe the 2 types of action tremors?
postural tremors - person maintains a part of body against gravity
intention tremors - produced with purposeful movement
Slow, writhing and twisting movements typically found in the UE more than in the LE are characterized by a disorder called:
athetosis
involuntary, rapid, irregular, and jerky movements seen with Huntington’s disease are characterized by a condition called?
choreiform
