The Canadian Movement Disorder Group


Ataxia is a term to describe loss of balance.

 The part of the brain that is involved in balance is at the back of the brain, attached to the brainstem, and is called the "Cerebellum". Damage to the cerebellum or its connections will result in unsteadiness of  walking, and clumsiness of hand and foot coordination.

Many conditions can cause the cerebellum to stop working normally.

Cause of Ataxia include a huge number of conditions:

Drug / Toxin induced cerebellar dysfunction:

These include drugs; Clonazepam, Tegretol, Phenobarb, Primidone, Dilantin and toxins including; acute alcohol intoxication, alcoholism, solvent abuse , lead / mercury

Trauma to the cerebellum

Head Injury

Endocrine Disorders (diseases of the glands that release hormones)


Nutritional Deficiencies

Vitamin B12 deficiency

Neoplastic (Tumor)

Paraneoplastic (Associated with a distant tumor)

Vascular Causes (Stroke)

These include; vasculitis (inflamation of blood vessels eg. Lupus), angioblastoma (a tumor of the blood vessels), embolism (a blood clot plugging a blood vessel), hemorrhage (a blood vessel rupturing and  bleeding into the cerebellum), and Von-Hippel-Lindau Syndrome (a disorder of blood vessel formation),

 Infectious Conditions Affecting the Cerebellum:

These include; syphilis, A.I.D.S., cerebellar abscess, Coxsackie virus,  Diptheria, Mumps, Polio, Typhus, Echovirus, Pertusis, Rubeola, Varicella, Infectious Mononucleosis, Mycoplasma, Infectious polyneuropathy, and Japenese B encephalopathy.

Degenerative Neurologic Conditions:

These include a large number of rare neurologic conditions as follows;  Olivo-ponto-cerebellar Degeneration (O.P.C.A.), Spinocerebellar Ataxias (S.C.A.1,2,3,4,5,6,7), Acute Disseminated Encephalomyelitis, Acute Intermintent Cerebellar Ataxia, Ataxia (with Retinitis  Pigmentosa, deafness, vestibullar abnormality, and intellectual dysfunction), Ataxia Telangiectasia, Cerebellar Ataxia (with deafness, anosmia, absent corneals, nonreactive pupils, and hyporeflexia),  Dentate cerebellar atxia, Familial Ataxia with macular degeneration, Familial intention tremor, ataxia, lipofuscinosis, Friedreichs ataxia, Hereditary ataxia (with intellectual retardation, choreoathetosis, and  eunuchoidism), Hereditary ataxia (with myotonia and cataracts), Hypertrophic interstitial neuritis, Marinesco-Sjogren Syndrome, Pelizaeus-Merzbacher disease, Periodic ataxia (with attacks of vertigo,  diplopia, and ataxia), Ataxia (with posterior, and lateral column difficulties, with nystagmus and muscle atrophy), Progressive cerebellar ataxia and epilepsy, Ramsy Hunt syndrome, and Roussy-Levy syndrome  

Inherited Metabolic Defects listed below:

Abetalipoprotienemia( Bassen-Kornzwieg Syndrome)

Ataxia, retinitis, acanthocytosis, malabsorption, acanthocytes, low cholesterol, low Beta-Lipoprotein, and absent LDL's

 Arginosuccinic aciduria

Siezures, hypotonia, hepatomegally, tufted friable hair, child onset, increasd Arginosuccinic acid in plasma

Ceroid lipofuscinosis (Kufs Disease)

Seizures, ataxia, myoclonus, dementia, Hypertension

Exam shows cerebellar, pyramidal, and extrapyramidal signs

Increased Lipopigments Ceroid, and Lipofuscin on brain biopsy, Peripheral leukocyte vacoules, and ceroid engorged vacuoles on conjunctival biopsy

Gm2 gangliosidoses (Tay-Sachs)( Sandhoffs)

Hyperacusis,myoclonus, seizures, developemental delay. Onset in first months of life.

Very low levels of beta-hexosaminidase in serum, Leukocytes, and cultured fibroblasts

Neutral amminoaciduria (Hartnup disease)

Pellagra type rash, and intermittent ataxia, triggered by sunlight or stress.


Severe retardation, siezures, myoclonus, in childhood

Ketoacidosis, and increased alanine in urine, and serum


I and II; Increased ammonia


Galactocerebrosidase Lipidosis (Krabbe Disease)

Early oset of retardation, spasticity, siezures and optic atrophy (blindness). Unlikely to live past 2 years. Macrocephaly,peripheral  neuropathy,hyporeflexia. Adult syndrome consists of leukodysrophy, cortical blindness, and spasticity. Peripheral neuropathy is rare.

Dx B-gaclactocerebrosidase measurement.

 Maple suryp urine disease

Rarely to live to age 5. Patients aquire spasticity, seizures, intermintant ataxia

Dx sweet smelling urine, increased amino (branched) acids in urine.

Metochromatic Leukodystrophy

Patients aquire retardation, leukodystrophy, psychosis, and dementia

Dx increased csf protein, peripheral neuropathy: Arylsulphatase def.

Niemann-Pick disease

Patients aquire retardation, seizures,ataxia

Dx by finding "Sea Blue" histiocytes in bone marrow, supranuclear  gaze palsy (upgaze)

Vacuolated Lymphocytes, Sphingomyelinase def.

Hereditary atactica polyneuritiformis (Refsum disease)

Chronic neuropathy(motor and sensory (HMSN type IV), ataxia, increase csf protien,retinitis

Dx increased serum Phytanic acid


Ataxia, photosensitivity, short stature, and mental retardation

Dx increased serum tryptophan

Wernike encephalopathy

Thiamine deficiency due to malnutrition, or Alcoholism

Congenital (I.E. present at Birth)

A variety of structural brain deffects can present as Ataxia including: Agenesis of vermis, Dysplasia, of cerebellum, Arnold-Chiari Malformation, Dandy Walker Malformation, Encephalocele, Platybasia and Hydrocephalus

Primary Emotional (reaction to stress)

Conversion reaction

Click Here for Ataxia Resources