MSD: Differential Diganosis

Dyarthira types + Apraxia

What causes Unilateral Upper Motor Neuron (UUMN) Dysarthria, what is its hallmark feature, and what metaphor could you use to remember it?

Site of damage = Upper Motor Neuron (UMN)

Hallmark feature = Milder dysarthria

Common etiologies:

• stroke w/ lesion being of a unilateral cortical UMN (nonprogressive)

• Trauma (nonprogressive)

• Tumour (could be either progressive/nonprogressive)

Like driving a car with one axel misaliged » structures pull to one side and make it less smooth and effortful to move

What are the non-speech body & OMA confirmatory signs of UUMN dys?

1. Controlateral facial droop (CN VII- facial)

2. Asymmetrical smile (reduced ROM on side controlateral to lesion CNVII)

3. Tongue deviation (tongue will veer to the weak side CNXII- hypoglossal)

4. Dysphasia (esp early on)

5. Often co-occuring w/ aphasia and/or apraxia of speech if lesion = left-sided ___________

6. Drooling from affected side of mouth

7. Contralteral vf weakness

8. Pseudobulbar affect (// more common in spastic)

What are the abnormal speech signs of UUMN dysarthria? And what subsystems of the speech system and what articulators are most affected?

1. A milder dysarthria

2. Impresicse consonsants due to face/tongue weakness: ARTICULATION

3. Slow rate for speech/oral mvts: ARTICULATION & PROSOY

4. Strained/harsh vocal quality due to vf weakness: PHONATION

What causes Hypokinetic dysarhtira, what is its hallmark feature, and what metaphor could you use to remember it?

Site of pb = basal ganglia pathology

• the basal ganglia = a deep subcortical structure wherein many NT are used. Imabalance of these NT results in mvt disorders e.g. low dopamine > Parkingson’s disease (PD)

Hallmark feature =

• Reduced amplitude of movement (mvts are smaller/shallower than normal)

• Rigidity

• Slow movement (bradykinesia)

• Tremors

  • (TRAP (tremours, ridigity, akinesia, postural difficulties)

Common etiologies:

• PD: presents several years after onset but in ~90% of patients who dvlp it and often precedes dyshagia (progressive)

• Parkinson’s plus syndromes/ atypical parkinsonism. often have mixed dys w/ hypokinetic + other dys type

• Stroke (basal ganglia lesions) (nonprogressive)

• Trauma (e.g. contact sports repeated head trauma) (nonprogressive)

Like driving an old car w/ that’s slow to respond, stiff/rigid, difficult to control speed/requires more effort

What are the non-speech body & OMA confirmatory signs of hypokinetic dys?

Overall Body:

1. Tremour - involunatry shaking, pill rolling

2. Rigidity - stiffness/resistance to mvt e.g. cogwheel (small kery mvts)

3. Akinesia - difficulty in initating mvts

4. Postural instability: difficulty maintiang balance

5. Bradykinesia: slowness of mvt

6. Reduced arm swing when walking

7. Micrographia: handwriting becomes small, cramped

8. Shuffling/festinating gait: short/hesitant steps, stooped posture

9. Freezing gait

10. Dysphagia

11. Cog decline ~ 50% of cases, 30-60% go on to develop dementia

12. Depression, apathy, sleep disturbances

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OMA:

13. Hypomimia/masked face: reduced facial expression/ appear unemotional

14. Reduced blink frequency (can cause watery eyes)

15. Tremor of jaw, tongue, lips as rest/in mvt

16. AMRs:ONLY DYS TYPE TO HAVE (potentially) RAPID AMRs » slow to start but can become rapid + impresise artic + usually regular rythm (SMRs=AMRs, though sometimes may have difficulty sequencing)

17. Tongue = slow (bradykinesia) + reduced ROM // strength = grossly normal

18. Drooling ++ common in PD due to reduced swallow frequency and effectiveness

What are the prominent abnormal speech features of hypokinetic dys?

1. Hypophonia/reduced loudness: due to weakness/rigidity of laryngeal muscles, reduced respiratory support, and lombard effect - an impairment in the audiotory feedback loop (ARTIC- RESP - SENSORY)

2. Monoloudness: weak/bradykinesia of laryngeal muscles - LARYNGEAL - PROSODIC

3. Monopitch: weak/bradykinesia of laryngeal muscles - LARYNGEAL - PROSODIC

4. Variable rate slow/rapid: poor control of mvt ARTIC + PROSODIC

5. Short rushes of speech: ARTIC + PROSODIC

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6. Imprecise consontants: bradykinesia, ARTIC

7. Inappropriate silences: PROSODIC (difficulty intiating mvt)

8. Rough, breathy voice: LARYNGEAL + RESPIRATOY

9. Dysfluencies: palilalia vs stuttering

10. Voice tremour

What causes Hyperkinetic Dysarthria, what is its hallmark feature, and what metaphor could you use to remember it?

Site of pb: basal ganglia pathology

Hallmark feature: excessive, abnormal involuntary mvts, + less commmon type

Common etiologies

• Huntington’s disease (progressive/degenrative - death of neurons in brain caused by inherited gene mutation » progressive loss of mvt, cognitive functions, mood )

• 89% undetermined

• Spasmodic dysphonia (voice disorder characterised by involuntary spasms of muscles controling the vocal folds)

• Tourette’s, focal myoclonus

• Toxic/metabolic

Like driving a car with a faulty steering wheel, sudden/unpredicatble mvts

What are the non-speech body & OMA confirmatory signs of hyperkinetic dys?

Hyperkinesias = excessive, involuntary mvts

• depends on type of mvt disorder: can be repetitive, brief/continuous, rythmic/irreg, large-amplitude, rapid/slow, unpredictable

What are the most prominent abnormal speech signs of hyperkinetic dysarthria?

1. Transient strained-harsh voice (bc of the atypical mvt)

2. Pitch breaks/voice arrest (bc of brief hyperadduction of VF)

3. Impresice articulation

4. Irregular articulatory breakdowns

5. Variable/excess loudness or pitch

6. Sudden forced inspiration/expiration

7. Prosodic difficulties: prolonged phonemes, variable rate, equal and excess stress, inappropriate silences (could be doing this as a compensatory startegy e.g. are you slowing down your speech or pausing on purpose to

8. AMRs depend on the type of hyperkinesisa:

• rate could be normal/slow

• artic could be normal when involuntary mvts ≠ occuring and then imparied when it is

• rhythm: regular if involuntary mvt ≠ occuring // irreg if interruptions/breaks due to involuntary mvts

9. SMRs = AMRs ( but you can’t predict when someone will get

What causes Ataxic Dysarthria, what is its hallmark feature, and what metaphor could you use to remember it?

Site of damage: cerebellum

• responsible for coordinaition, balance/posture, motor learning

• integrates sensory info to coordinate motor function (e.g. proprioception)

Hallmark feature:

• impaired coordination

• slurred, irreg, unsteady speech (drunk sounding)

• Speech worsens w/ alcohol

Causes:

• Spinocerebellar ataxia (group of degenerative/progressive disorders that all affect cerebellum)

• Friedreich’s ataxia (degenerative)

• Multiple sclerosis (often mixed w/ spastic)

• Stroke (cerebellum)

• Tumour (cerebellum)

• Focal trauma (cerebellum)

Like driving a car on a bumpy/uneven road

What are the non-speech body & OMA confirmatory signs of ataxic dysarthria?

1. Wide-based gait: often used to compensate/ improve balance/stability

2. Dysmetria: Over/under shooting intended target

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3. Truncal instaiblity: difficulity maintaining upright posture

4. Head tremors/titubation: rhythmic tremor of head/body

5. Nystagmus: rapid, jerky eye mvts at rest

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OMA non-speech

5. AMRs

• Rate: normal/somewhat slow

• Artic: prescision, loudness and/or pitch vary/ = irregular

• Rhythm: Usally irreg in timing

5. SMRs = AMRs

6. Poor phonatory-respiratory coordination: incoordination bt onset of exhale and phonation, can initate speech late in breath cycle causing a softer/weaker voice

7. Bite cheek/tongue while talking or eating bc of poor coodination/dysmetria

What are the prominent abnormal speech signs of ataxic dysarthira?

1. Irreg articulatory breakdowns: ARTIC

2. Distored vowels: ARTIC + PROSODIC

3. Execess and equal stress: PROSODIC

4. Prolonged phonemes: ARTIC/PROSODIC

5. Varations/irregular loudness/monoloudness: due to poor coordination of laryngeal muscles LARYNGEAL, RESPIRATORY, PROSODIC

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6. Slow rate: PROSODIC

7. Prolonged intervals/pauses bt sllables/words/phrases- irreg rhythm

8. Telescoping speech (slurring syllables/words tgt): ARTIC

9. Imprecise consonants/ slurred/drunk speech: ARTIC

Write summary table of dysarthira + apraxia types.

Write Summary Table comparing AMRs/SMRs of each dysarthira type + AOS

What causes flaccid dysarthria, what is its hallmark feature, and what metaphor could you use to remember it?

Site of damage: LMN

Hallmark feature: weakness

Common Etiologies

• Stroke (in brainstem affecting CN)

• Trauma

• Tumour

• Myasthenia gravis (disease of neuro-muscular junction preventing NT from binding to receptor sites)

• Guillaine Barre Syndrome (GBS auto-immune disease often occurs after virus)

• Bell’s palys (facial muscle paralysis)

Like driving w/ a flat tire

What are the non-speech body & OMA confirmatory signs of flaccid dysarthria?

1. Hypotonia = reduced muscle tone (bc the muscle fibres are not getting the signals they should)

2. Atrophy (tongue and body)

3. Fasciculations (tongue (on floor of mouth) and body)

4. AMRs

• Rate: Slow

• Artic: Impresice due to wekaness

• Ryhtm: regular

5. SMRs = AMRs (can have some irreg // not as much as ataxic)

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6. Hyporeflexia (diminished/absent reflexes)

7. Weak cough

8. Drooling

9. Dysphasia/nasal regurgitation

What are the prominent abnormal speech signs of flaccid dysarthira?

1. Hypernaslity - VELOPHARYNGEAL

2. Nasal emission - VELOPHARYNGEAL

3. Audible inspiration/ stridor - LARYNGEAL (bc of weakness of muscles controling VF » as air comes out there’s obstruction to the airflow causing turbuluent

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4. Continuous breathiness - LARYNGEAL

5. Horase voice - LARYNGEAL

6. Diplophonia - LARYNGEAL

4. Monopitch, monoloud - LARYNGEAL + RESPIRATORY

5. Short phrases - LARYNGEAL + RESPIRATORY

4. Imprecise consonants - ARTIC

5. Vowel distortions - ARTIC

What causes Spastic Dysarthria, what is its hallmark feature, and what metaphor could you use to remember it?

Site of damage = BILATERAL UMN

Hallmark = slowness, effortful resistance to mvt/reduced ROM

Common etiologies:

• Bilateral strokes

• Cerebral palsy

• Motor neuron disease (can be mixed w/ flaccid)

• Multiple sclerosis (can be mixed w/ ataxic)

• Tumours

• Trauma

Like driving with the handbrake up

What are the non-speech body & OMA confirmatory signs of spastic dysarthria?

1. Hypertonia = increased muscle tone

2. Pseudobulbar affect/emotional libality (e.g. inappropriate crying/laughing bc UML damange impacts neural pathways impacting emotions)

3. Fatigue esp after prolonged muscle use

4. AMRs:

• Rate: slow

• Artic: imprecise, effortful/ ^ resistance to mvt

• Rythm: regular

5. SMRs = AMRs

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6. Hyperflexia

7. Balance/gait issues

8. Dysphagia

9. Drooling

What are the prominent abnormal speech signs of spastic dysarthira?

1. Slow Rate - ARTIC

2. Imprescise consonants - ARTIC (bc reduced ROM of articulators: tongue, lips, jaw, soft palate)

3. Strained-strangled harsh voice - LARYNGEAL (bc the VF come tgt too tight)

4. Pitch breaks - LARYNGEAL (incoordination of VF)

5. Low pitch - LARYNGEAL (limited tone in VF)

6. Short phrases - LARYNGEAL, RESPIRATORY, VELOPHARYNGEAL, ARTICULATION (bc of reduced resp support)

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6. Excess and equal stress (bc slow rate makes it sound like this)- PROSODIC

7. Distorted vowels - ARTIC

8. Hypernasality - VELOPHARYNGEAL

9. Breathy - LARYNGEAL

10. Monopitch - LARYNGEAL

11. Monoloud - LARYNGEAL

What is apraxia of speech? What causes it? What is its hallmark feature?

an impairment in planning and programming stage of speech prod that can exist in the absence of physiological disturbances associated w/ dysarhitra and in absence of lang impairment (// often co-occurs with these two (dys and Broca’s expressive aphasia)

Site of pb = almost always pathology of left cerebral hemipshere

Hallmark feature = impairement in articulatory and prosodic (rate/rythm) features of speech

Common etiologies:

• Stroke (most common)

• 1st sign of a neurodegentrative disease:

  • PSP (progressive superneuclear palsy)

  • CBD (corticobasal degeneration)

  • PPA (primary progressive aphasia)

What are the non-speech body & OMA confirmatory signs of apraxia?

1. Right sided weakness and spasticity (if secondary to a stroke)

2. Limb apraxia: person has ability to move // cannot plan purposeful mvts, or mimic aka bilateral deficits in purpsive limb mvts that can’t be explained by impairments in strength, mobility, sensation or coordination (important to consider if needing an AAC)

3. Nonverbal oral apraxia = inability to imitate or follow commands to perform volitional mvts of speech structures e.g. cough, blow, click tongue » NOT due to not being able to understand instructions, senosry or neuromuscular deficts bc reflexes of these tasks are perseved

4. If isolated AOS rarely compain of chewing/swallowing dificulties so if they do think about accompanying dysarthira

5. Right lower face and lingual weakness may be present + UUMN dyarthira (if secondary to stroke)

What does AMRs and SMRs stand for?

Alternating motion rates

Sequential Moiton Rates

What are the components of a base otor speech exam? What do you add on for assessment and differential diagnosis of AOS?

1. Case history

2. CN Exam/ OMA

3. Conversation

4. Reading

5. AMR/SMR

6. Motor speech tasks (e.g. volume/pitch modulation)

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Additional

• Mutlisyllabic words: caterpillar

• Words of increasing length: sharp, sharpen, sharpening

• Nonsense words (harder for them bc they have to plan a novel sequence)

• Automatic speech tasks e.g. counting, days of week, name/address, singing (less likely to have difficulty bc they are so well trained/rehearsed)

• Aphasia battery

What are the abnormal speech features of AOS in terms of prosody?

PROSODIC

1. Slow rate esp if more than 1 syllable (can be both a feature + compensatory strat)

2. Speech = effortful/halting (pauses, hesitations)

3. Syllable segregation/segmentation - sepeate words into sylalbles » speech sounds choppy

4. Prolonged vowels in multisyllable

5. Equal and excess stress

What are the abnormal speech features of AOS in terms of articulation?

ARTICULATION

1. Sound distortions - esp affricates and fricatives bc these require high level coordination bt respiration and phonation

2. Consonants substitutions (rare in dysarthira)

• perseverative

• anticipitory

3. Increasing errors w/ increasing complexity

• Words increasing in length

• low freuqency syllables

• syllables w/ more phones e.g. strong vs me

• Consonant cluster w/i syllables

• Coples cluster transitions

4. Nonsense words = harder

5. Difficulty producing stress on words w/ weak onsets

6. Inconsistent errors // this depends on the task and stimulus context

• consistent during blocked practice: cat cat cat» bc they only have to retrieve motor plan once

• random practice = more variable/inconsistent errors e.g. cat, dog, mouse, dog »bc they have to retrieve motor plan ++ times

  • important to consider for treatment: random practice challenges both motor-plan accuracy and retrieval

What are the abnormal speech features of AOS in terms of fluency?

• Effortful visible and audible groping for artic postures

• Sound and syllable repetitions

• Difficulty initating utterances e.g. word

• Often aware of errors and attempt to self-correct

• False artic starts/ restarts