Ataxia

Core Symptoms (3)

1) Difficulty with balance and gait 2) Clumsiness of the hands 3) Dysarthria

Clinical Manifestations of Cerebellar Dysfunction (6)

1) Stance and Gait 2) Limb Coordination 3) Tremor 4) Muscle Tone 5) Speech 6) Ocular Motor Fluctuations

Ataxia

A neurological disorder characterized by clumsiness (lack of coordination) of voluntary movements that is produced by dysfunction of the cerebellum or cerebellar pathways

Recessive Inherited Ataxias

Ataxia is hidden in the genes of both healthy parents and the child can develop the disease only if they inherit the defective gene from both parents (1) X-linked Recessive - due to genetic deficit on the X-chromosome Appears only in males and is carried forward by the females who go unaffected (2) Friedreich Ataxia - most common cause of hereditary ataxia Age of onset - before 20 Clinical features: dysarthria, sensory loss, pyramidal degeneration, cardiomyopathy, and diabetes There is an axon-less peripheral neuropathy

Speech

Cerebellar Dysarthria - characterized by an altered articulation of words and abnormal fluency of speech May be a simple slowing of speech or a slurring and scanning dysarthria where words are broken into syllables

Tremor

Cerebellar tremor is defined as kinetic (intention) tremor

Both sides ataxia

Conditions affecting both sides of the cerbellum or its connections cause imbalance, gait ataxia, right and left extremity lack of coordination, and dysarthria

Symptoms appear suddenly

Could be caused by: Head trauma stroke cardiac or pulmonary arrest infection tumor in cerebellum exposure to certain drugs or toxins

Classification - Sporadic

Degenerative Stroke or Tumor Toxic/Metabolic Autoimmune

Stance and Gait

Difficulties in equilibrium are the first symptoms of most cerebellar syndromes Wide based stance and gait Gait being characterized by staggering, irregularity of steps, and lateral veering

Muscle Tone

Hypotonia is a typical cerebellar sign Hypotonia - a decrease in the normal resistance offered by muscles to passive manipulation

Hemispheric Cerebellar Dysfunction

Involve motor planning and control of fine motor movements

Midline Cerebellar Dysfunction

Involves axial control, including vestibular function, eye movements, and balance and postural stability

Dysarthria

Motor speech disorder manifested as clumsy, slurring, poorly modulated speech

Autoimmune Ataxia

Ms, acute demyelination encephalmyetis, Guillian-Barre syndrome, can all present acutely with ataxia Characterized by symmetrical weakness which usually affects lower limbs first and then rapidly (hours/days) progresses in ascending fashion

Degenerative Ataxia

One prominent cause of progressive ataxia in older adults is multiple system atrophy MSA isa disease of unknown cause characterized by a loss of oligodendroglia and neurons in multiple structures throughout the brains

Dominant Inherited Ataxias

Passed from an affected parent to child, each with having a 50% chance of inheriting the gene abnormality

Symptoms appear gradually

Possible causes include: deficiencies in vitamin E or B12 congenital abnormalities such as cerebellar deformity remote effects of cancer somewhere in the body slow growing tumors exposure to certain drugs or toxins

One sided ataxia

Stroke, tumors, abscesses, and trauma are more likely to affect just one side of the cerebellum and therefore cause one-sided ataxia

Toxic/Metabolic Ataxia

Toxic can be caused by alcohol - acute and chronic (1) Acute effects of alcohol produce the typical 'drunk' motor impairments (true ataxia) (2) Chronic alcohol can lead to irreversible cerebellar damage (vermis and anterior lobe) Metabolic - celiac disease or sprue can lead to ataxia Celiac disease is a gluten sensitive enteropathy (intestinal disease) with malabsorption. Hypoxia, Vitamin B1, B12, E, and Zinc deficiency, hypothyroidism, and hypoglycemia

Stroke or Tumor Ataxia

Vascular lesions, infections, and structural lesions to the cerebellum or cerebellar pathways can lead to ataxia

Etiology

Ataxias present as chronic progressive diseases starting in infancy (early onset) or adulthood (late onset) A few forms of ataxia are present as acute diseases, such as alcoholic ataxias, whereas other forms present as acute recurrent diseases (episodic ataxias)

Classification - Genetic

Due to gene defect or mutation Dominant inherited ataxias Recessive inherited ataxias

Ocular Motor Fluctuations

Fixation instability with involuntary saccades taking the eyes away from the fixation target followed by corrective saccades returning the eyes to the target

Treatment

There is no treatment for ataxia Physical therapy, occupational therapy, and speech therapy

Limb Coordination

Three main abnormalities of voluntary movements: 1) Asynergia - Movements are broken into isolated subsequent steps and lack easiness and smoothness 2) Dysdiadochokinesia - There is an impaired performance of rapidly alternating movements 3) Dysmetria - There is an abnormal excursion in movements and errors in reaching a precise target