Spastic Dysarthria

Question 1

Spastic Dysarthria: Overview

Answer 1

Caused by bilateral damage to activation pathways of the CNS.

Can manifest in any or all of the components of speech production, but is rarely confined to only a single component.

Is a problem of neuromuscular execution.

Question 2

Spastic Dysarthria: Characteristics

Answer 2

Characteristics reflect the combined effects of weakness and spasticity in a manner that slows movement and reduces range and force.

Clinical features reflect the effects of excessive muscle tone (hypertonicity) and weakness on speech.

Can exhibit clonus

Major abnormalities that affect movement in spastic paralysis:

• Spasticity
• Weakness
• Reduced ROM
• Slowness of movement

Question 3

Clonus

Answer 3

A repetitive reflex contraction that occurs when a muscle is kept under tension

Question 4

Etiologies

Answer 4

Any process that damages the activation pathways bilaterally can cause spastic dysarthria.

Can include:

• Degenerative
• Vascular
• Congenital
• Trauma
• Inflammatory
• Toxic/Metabolic Diseases

Question 5

Vascular Disorders

Answer 5

Strokes in the following arteries can lead to spastic dysarthria:

• Internal carotid
• MCA
• PCA
• ACA (sometimes)

Lesions are needed in both hemispheres to produce the bilateral damage associated with spastic dysarthria.

Some spastic dysarthria patients have had multiple infarcts

Question 6

Binswanger’s Disease

Answer 6

A term sometimes applied to patients with vascular dementia.

The bilateral lesions associated with BD can affect the UMN pathways and sometimes lead to spastic dysarthria and dysphagia.

Question 7

Moyamoya Disease

Answer 7

A chronic, progressive vascular disease most frequently affecting children and young adults.

Can cause stroke and intracranial hemorrhage that can lead to S&L deficits, including spastic dysarthria.

Question 8

Degenerative Diseases

Answer 8

When spastic dysarthria is the primary manifestation of neurodegenerative disease, the disorder is sometimes referred to as Progressive Pseudobulbar Palsy.

Spastic dysarthria can emerge in people with neurodegenerative apashia and apraxia of speech.

Question 9

Primary Lateral Sclerosis (PLS)

Answer 9

Subcategory of motor neuron disease (degenerative) that often begins around age 50-60.

Can present with spastic dysarthria with or without dysphagia, and dysarthria is eventually present in many cases.

Question 10

Cerebral Palsy

Answer 10

A congenital disorder that is very often associated with spastic dysarthria, which can be severe.

Question 11

Leukoencephalitis

Answer 11

An inflammatory demyelinating disease that affects the white matter of the brain or spinal cord.

The bilateral and multifocal effects can affect UMN pathways and cause spastic or mixed dysarthrias.

Question 12

Patient Perceptions and Complaints

Answer 12

• Speech is slow or effortful
• Fatigue when speaking
• Must speak more slowly to be understood, but also admit they can’t speak any faster.
• Swallowing complaints often in the oral and pharyngeal phases.
• Drooling (more than any other dysarthria type)
• Gagging when brushing teeth
• Difficulty controlling emotions (more than any other dysarthria type)

Question 13

Non-Speech Oral Mech

Answer 13

• Dysphagia is common and can be severe
• Face may be weak bilaterally; range of lips may be decreased.
• Face may be in a fixed, subtle smiling posture.
• Tongue is fully symmetric but ROM may be reduced.
• Slow and reduced ROM in AMRs
• Symmetric but slow palate

Question 14

Speech

Answer 14

Conversational speech, reading, AMRs, and vowel prolongation are most useful tasks.

Spastic dysarthria is associated with impaired movement patterns rather than weakness of individual muscles

Question 15

Speech: Distinguishing Features

Answer 15

Strained-harsh VQ 
Monopitch 
Monoloudness 
Slow speech rate
Slow and regular AMRs