Constraints on motor control: overview of neuro impairments (ppt)

Assessment of mvmt (nature)

-(interaction of ITE)

kinematics

- dynamic assessment of linear and angular kinematic parameters

-position and displacement

-velocity and acceleration

-relative motion and 3D motion

-stride length, step length

kinetics

-study of forces that cause mvmt and the resultant energetics

-acceleration approach

-impulse-momentum approach

-work-energy approach

-GRF

Strategy/Pattern of mvmt

-observational mvmt analysis

Strategy level

-observational mvmt analysis: how does pt move?

-qualitative

-speed, timing, directional control, smoothness of mvmt, accuracy, adaptability

-ex: improper timing of components of STS, decreased ant. wt. shift, slow, no involuntary mvmt, STS completed with more effort, less adaptable

Scales for observational mvmt analysis

-MAS: motor assessment scale

-sections of FuglMeyer

Constraint level

-impairment of body structure

-musculoskeletal (ROM, muscle strength, alignment, joint intrgrity)

-neuromuscsular (NM connectivity, neural conduction)

-cognitive/perception (sensoryy, perception, cognition)

-major part of assessment of motor control

Function level

-activities

-participation

-social context

-does mvmt transfer to ADLs (ex: STS in situation where urgent need to use restroom)

Cortical motor impairments

-muscle weakness

-abnormal muscle tone

-loss of individuation

-abnormal synergy

-abnormal co-activation/activation

Sub-cortical motor impairments

-cerebellum related

-hypotonia

-discoordination

-dysmetria

-dysdiadochokinesia

-intention tremors

-impaired error correction

-basal ganglia related

-hypokinesia

-rigidity

-tremor

-hyperkinetic disorders

-dystonia

Muscle weakness results in

-paresis/paralysis

-secondary MSK changes (contractures, tightness)

-habitual adaptations/compensations (ex: leg length discrepancies)

-it's important to examine and document muscle weakness in a person with NM (including CNS) pathology

Muscle weakness assessments

-exam of muscle strength

-MMT

-instrumented testing

-functional testing (ex: 30 s STS, 5 times STS)

Document considerations for muscle weakness assessments

-testing of specific/grps of muscles

-position testing was done

-side tested

-MMT grade vs type and degree of change

-factors influencing strength (atrophy, cognition)

-muscle endurance (fatigue)

Muscle weakness tx

-strategies to improve neural activation (recruitment of paretic muscles)

-facilitation techniques

-task-specific training

-biofeedback

-functional e-stim

Tx of impaired strength

-progressive resisted exercises

-isokinetic equipment

-task-specific training

Effect of strength training on spasticity

-tone has nothing to do with force generation

-you can have a spastic muscle that is strong or weak.

-weakness comes from disuse

-STRENGTH TRAINING DOES NOT HAVE AN EFFECT ON TONE

-tone is passive, strength is active

Range of muscle tone

Flaccidity - Hypotonia - Normal Range of Muscle Tone - Hypertonia - Rigidity

Hypertonicity

-heightened resistance to passive mvmt

Spasticity

-velocity dependent

Rigidity

-velocity independent

-lead pipe

-cogwheel

Hypotonicity

-reduction in the stiffness of a muscle to lengthening

-commonly seen in Down's syndrome, dev. delays, spinocerebellar lesions

Language of Spasticity

-This term is used clinically to describe a wide range of behaviors

-hyperactive stretch reflexes

-abnormal posturing of the limbs

-excessive co-activation of antagonist muscles

-associated mvmts

-clonus

-stereotyped mvmts synergies

-Motor disorder characterized by veloctiy-dependent increase in resistance of muscle/muscle grps to passive stretch (muscle tone)

-lesion in descending motor systems (UMN)

-no agreement on role of spasticity in the loss of functional performance: SPASTICITY DOES NOT IMPAIR FUNCTION. Teach the brain to learn WITH spasticity.

-contemporary evidence: tx practices primarily focused on reducing spasticity/hypertonicity may have limited impact on helping pts

-only botox and sx reduce spasticity

Muscle tone assessments

-exam of muscle tone

-difficult to ID a best practice related to assessment of muscle tone

-Focus on 3 issues relating to functional problem when evaluating spasticity

-ID clinical pattern of motor dysfunction and its source

-ID pts ability to control muscles involved in clinical pattern

-differentiating role of muscle stiffness and contractures

Muscle tone assessments 2

-Abnormal muscle tone

-observational assessment (imprecise, not objective)

-Clinical methods

-passive mvmts across joints

-pendulum drop test: pt sitting on raised table, lift leg and drop. Watch number of swings.

-behavioral indicators

-Clinical scales

-modified Ashworth scale

-modified Tardieu scale

-Instrumented measures

Modified Ashworth scale (EXAM Q)

-measures level of resistance to passive mvmt

-doesn't eval the velocity of passive joint mvmt, angle of contraction outbreak or potential tendon retraction

-popular in clinical practice-ease and speed of use

Limitations of modified Ashworth scale

-poor-moderate inter-rater reliability

-not-velocity dependent

-doesn't consider effect of contractures and resultant decreased ROM

Modified Tardieu scale

-measures muscle resistance and velocity of the mvmt that induces muscular contraction

-spacticity is assessed with 3 velocities (low, normal and fast)

-considers velocity of passive joint mvmt, angle of contraction outbreak and potential tendon retraction

-better inter and intra rater reliability

Modified Tardieu scale limitations

-more evidence in kids than adults

-more rsrch req to establish reliability and specificity of the scale

What is a commonly used measure to quantify spasticity of a muscle?

Spasticity and abnormal synergies result in muscle weakness. Is this statement false?

Loss of Individuation

-fractionated mvmt

-selective muscle activation (or joint control)

-isolated mvmt

-ability to selectively activate a muscle (or set of muscles) allowing isolated joint mvmt

Abnormal synergies

-massed patterns of mvmt

-abnormal coupling of muscles and joints into characteristic mvmt patterns

In the rehab world synergy means

-abnormal/disordered motor control

synergy

-grp of muscles working together

Individuation assessments

-observation

-resting position (usually UE or LE)

-mvmts (usually UE or LE)

-clinical measures

-Fugl Meyer assessment (FMA)-stroke specific

-motor assessment scale (MAS)

Individuation txs

-treatment approaches for individuation of mvmt

-neurophysiological approaches

-neurofacilitation (PNF and NDT)

-functional rehab approaches

-dynamic spasticity physio

-biomechanical approaches

-joint approx

-proper alignment and support for weak muscles

UE flexion synergy components

-scapular retraction/elevation or hyperext

-shoulder abd, ext rot

-elbow flexion

-forearm supination

-wrist and finger flexion

LE flexion synergy components

-hip flexion,ext rot

-knee flexion

-ankle DF

-toe flexion

UE extension synergy components

*scapular protraction

*SHOULDER ADDUCTION

*elbow extension

*forearm pronation

*wrist and finger flexion

LE extension synergy components

-hip extension, internal rotation

-knee extension

-ankle plantarflexion

-toe plantarflexion

Abnormal synergies assessments

-exam of synergies

-observation and description of

-resting posture of arm/leg

-quality and nature of voluntary mvmt

-presence of associated mvmts

Abnormal co-activation

-aka co-contraction

-IS A REFLEX PRESENTATION

-increased co-activation (proximal>distal)

-altered co-activation related to chngs in

-muscle activation/recruitment

-passive muscle structures (stiffness, viscosity, inertia)

-agonist-antagonist activation

-control of long latency reflexes (M1, M2, M3)

-stretch-reflex modulation during voluntary mvmts

-muscle lengthening/shortening velocity

Abnormal co-activation assessments

-Exam of muscle activation

-observational analysis of mvmts

-EMG during mvmts

-functional mobility assessments

Abnormal activation: cerebellar pathology

-hypotonia

-incoordination

-intention tremor

-ataxia

-impaired error correction/impaired motor learning

Abnormal activation BG pathology

-hypokinetic disorders (PD)

-bradykinesia/akinesia

-rigidity

-resting tremor

-hyperkinetic disorders (HC)

-hemiballismus

-athetosis

-chorea

-dystonia

Abnormal co-activation assessment

-exam of cerebellar function/coordination

-non-equilibrium tests

-FTN, FTF, HST, pronation/supination

-equilibrium tests

-postural control assessment

-balance testing

Abnormal co-activation assessment (documentation)

-does pt have difficulty initiating or terminating functional mvmt?

-is the mvmt slow?

-is the mvmt smooth and fluid or jerky?

Which of the following impairments is associated with BG pathology

Dystonia results from injuries to the motor cortex (T/F)

Somatosensory deficits

-DCML: light touch, proprioception, vibration

-Anterolateral spinothalamic tract related (pain)

-S-I vs.S-II lesions (cortical sensations)

Parietal cortex related (multimodal integration)

-Association cortices: higher order sensory/perception/attn disorders (stereognosis, barognosia)

-visual deficits

-vestibular deficits

Touch awareness (discrim touch)

-stimulus: light touch with cotton ball

-response: eyes close, pt says yes or signals when felt

-score: % of correct responses out of total

Touch localization (discrim)

-stimulus: light touch with cotton ball

-response: eyes close, point to location of touch

-score:record error in accuracy of location

bilateral touch (sensory extinction)

-stimulus: touch pt on 1 vs both sides of body w/fingertips

-response: eyes close, pt says 1 or 2 to indicate how. many felt

-score: record presence of sensory extinction

touch pressure threshold (discrim)

-stimulus: use range of filaments

-response: eyes closed, pt says when they feel stimulus

-score:score number of thinnest filament felt

Two-point discrimination (discrim)

-stimulus: using 2 paper clips apply points to skin, move pts together

-response: pt responds 1 or 2 or can't tell

-score:% of correct responses out of total

vibration (proprio)

-stimulus: apply tuning fork to skin

-response:pt indicates when they feel stimulus

-score: % of correct responses

joint position (proprio)

-stimulus: passively position joint in flex or ext

-response: eyes closed, pt mimics position with contralateral limb

-score: % of correct responses out of total

joint motion (proprio)

-stimulus: passively move joint into flex/ext

-response: eyes closed pt reports whether joint is bending or straightening

-score: % correct

stereognosis (proprio)

-stimulus: place series of small objects in pts hand

-response: pt names object

-score: % correct

sharp/dull (pain)

-stimulus: randomly apply sharp and blunt end of safety pin to skin

-response: eyes closed, pt says sharp or dull

-score: % correct

temp

-stimulus: apply cold (40 F). or hot (115F) to pts skin

-response: pt indicates hot or cold

-score: % correct

Association cortices impairments

-spatial impairments

-hemineglect

-extinction

-non-spatial impairments

-attn probs

-decreased focused attn

-decreased sustained attn (vigilance)

-decreased attn to new stimuli

-difficulty reorienting attn (distractability)

-difficulty disengaging (perseverance)

Cognition

-ability to process, sort, retrieve and manipulate info

perception

-integration of sensory impressions into psychologically meaningful info

Cog/percept impairments

-affect ability to move effectively and efficiently in the environ

Cognitive impairments

-attn deficits

-orientation deficits

-memory deficits

-deficits in prob solving

-decreased arousal/level of consciousness

-difficulty with explicit and implicit motor learning

perceptual impairments -

-body image/scheme disorders

-unilateral spatial neglect

-r/l discrimination

-spatial relation disorders

-topographic orientation (high, low, wide, narrow)

-figure-ground perception

-position in space

-apraxia

-limb apraxia (ideomotor: clumsy vs ideational: confuse toothbrush and haribrush)

-constructional apraxia

-dressing apraxia

Exam of cog/percept

-mini mental state test (MMS)

-montreal cognitive assessment (MoCA)

-visual object and space perception battery (VOSP)

-battery of perception tests

A therapist suspects that a pt with disequilibrium may have a cerebellar pathology. However, several systems are involved for balance and equilib. Which of the following tests may help the therapist to rule in or out cerebellar pathology?