Ataxia is a
neurological sign consisting of lack of voluntary
coordination of muscle movements that can include
gait abnormality
Gait abnormality is a deviation from normal walking (gait). Watching a patient walk is the most important part of the neurological examination. Normal gait requires that many systems, including strength, sensation and coordination, function in an ...
, speech changes, and abnormalities in eye movements. Ataxia is a clinical manifestation indicating dysfunction of the parts of the
nervous system that coordinate movement, such as the
cerebellum. Ataxia can be limited to one side of the body, which is referred to as hemiataxia. Several possible causes exist for these patterns of neurological dysfunction. Dystaxia is a mild degree of ataxia.
Friedreich's ataxia
Friedreich's ataxia (FRDA or FA) is an autosomal-recessive genetic disease that causes difficulty walking, a loss of sensation in the arms and legs, and impaired speech that worsens over time. Symptoms generally start between 5 and 20 year ...
has gait abnormality as the most commonly presented symptom. The word is from
Greek α-
negative prefix+ -τάξις
rder= "lack of order".
Types
Cerebellar
The term
cerebellar ataxia
Cerebellar ataxia is a form of ataxia originating in the cerebellum. Non-progressive congenital ataxia (NPCA) is a classical presentation of cerebral ataxias.
Cerebellar ataxia can occur as a result of many diseases and may present with sympto ...
is used to indicate ataxia due to dysfunction of the cerebellum. The cerebellum is responsible for integrating a significant amount of neural information that is used to coordinate smoothly ongoing movements and to participate in
motor planning. Although ataxia is not present with all cerebellar
lesion
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals.
Types
There is no designated classif ...
s, many conditions affecting the cerebellum do produce ataxia.
People with cerebellar ataxia may have trouble regulating the force, range, direction, velocity, and rhythm of muscle contractions.
This results in a characteristic type of irregular, uncoordinated movement that can manifest itself in many possible ways, such as
asthenia,
asynergy, delayed reaction time, and
dyschronometria. Individuals with cerebellar ataxia could also display instability of gait, difficulty with eye movements,
dysarthria
Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. In other words, it is a condition in which problems effective ...
,
dysphagia,
hypotonia
Hypotonia is a state of low muscle tone (the amount of tension or resistance to stretch in a muscle), often involving reduced muscle strength. Hypotonia is not a specific medical disorder, but a potential manifestation of many different diseases ...
,
dysmetria, and
dysdiadochokinesia.
These deficits can vary depending on which cerebellar structures have been damaged, and whether the lesion is bi- or unilateral.
People with cerebellar ataxia may initially present with poor balance, which could be demonstrated as an inability to stand on one leg or perform
tandem gait. As the condition progresses, walking is characterized by a widened base and high stepping, as well as staggering and lurching from side to side.
Turning is also problematic and could result in falls. As cerebellar ataxia becomes severe, great assistance and effort are needed to stand and walk.
Dysarthria
Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. In other words, it is a condition in which problems effective ...
, an impairment with articulation, may also be present and is characterized by "scanning" speech that consists of slower rate, irregular rhythm, and variable volume.
Also, slurring of speech, tremor of the voice, and
ataxic respiration may occur. Cerebellar ataxia could result with incoordination of movement, particularly in the extremities. Overshooting (or hypermetria) occurs with finger-to-nose testing and heel to shin testing; thus,
dysmetria is evident.
Impairments with alternating movements (dysdiadochokinesia), as well as
dysrhythmia, may also be displayed. Tremor of the head and trunk (
titubation
A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, ...
) may be seen in individuals with cerebellar ataxia.
Dysmetria is thought to be caused by a deficit in the control of interaction
torques in multijoint motion.
Interaction torques are created at an associated joint when the primary joint is moved. For example, if a movement required reaching to touch a target in front of the body,
flexion at the
shoulder would create a torque at the
elbow, while
extension
Extension, extend or extended may refer to:
Mathematics
Logic or set theory
* Axiom of extensionality
* Extensible cardinal
* Extension (model theory)
* Extension (predicate logic), the set of tuples of values that satisfy the predicate
* Ext ...
of the elbow would create a torque at the
wrist. These torques increase as the speed of movement increases and must be compensated and adjusted for to create coordinated movement. This may, therefore, explain decreased coordination at higher movement velocities and accelerations.
*
Dysfunction of the vestibulocerebellum (
flocculonodular lobe) impairs balance and the control of eye movements. This presents itself with
postural instability, in which the person tends to separate his/her feet upon standing, to gain a wider base and to avoid titubation (bodily oscillations tending to be forward-backward ones). The instability is, therefore, worsened when standing with the feet together, regardless of whether the eyes are open or closed. This is a negative
Romberg's test, or more accurately, it denotes the individual's inability to carry out the test, because the individual feels unstable even with open eyes.
* Dysfunction of the
spinocerebellum (
vermis and associated areas near the midline) presents itself with a wide-based "drunken sailor"
gait (called truncal ataxia),
characterised by uncertain starts and stops, lateral deviations, and unequal steps. As a result of this gait impairment,
falling is a concern in patients with ataxia. Studies examining falls in this population show that 74–93% of patients have fallen at least once in the past year and up to 60% admit to fear of falling.
* 'Dysfunction of the
cerebrocerebellum
The anatomy of the cerebellum can be viewed at three levels. At the level of gross anatomy, the cerebellum consists of a tightly folded and crumpled layer of cortex, with white matter underneath, several deep nuclei embedded in the white matter ...
' (lateral hemispheres) presents as disturbances in carrying out voluntary, planned movements by the extremities (called appendicular ataxia).
These include:
**
Intention tremor (coarse trembling, accentuated over the execution of voluntary movements, possibly involving the head and eyes, as well as the limbs and torso)
** Peculiar writing abnormalities (large, unequal letters, irregular underlining)
** A peculiar pattern of
dysarthria
Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. In other words, it is a condition in which problems effective ...
(slurred speech, sometimes characterised by explosive variations in voice intensity despite a regular rhythm)
** Inability to perform rapidly alternating movements, known as dysdiadochokinesia, occurs, and could involve rapidly switching from
pronation to
supination of the forearm. Movements become more irregular with increases of speed.
** Inability to judge distances or ranges of movement happens. This dysmetria is often seen as undershooting,
hypometria, or overshooting,
hypermetria, the required distance or range to reach a target. This is sometimes seen when a patient is asked to reach out and touch someone's finger or touch his or her own nose.
** The rebound phenomenon, also known as the loss of the check reflex, is also sometimes seen in patients with cerebellar ataxia, for example, when patients are flexing their elbows isometrically against a resistance. When the resistance is suddenly removed without warning, the patients' arms may swing up and even strike themselves. With an intact check reflex, the patients check and activate the opposing triceps to slow and stop the movement.
** Patients may exhibit a constellation of subtle to overt cognitive symptoms, which are gathered under the terminology of
Schmahmann's syndrome.
Sensory
The term
sensory ataxia
Sensory ataxia is both a symptom and a sign in neurology. It is a form of ataxia (loss of coordination) caused not by cerebellar dysfunction but by loss of sensory input into the control of movement.
Sensory ataxia is distinguished from cerebellar ...
is used to indicate ataxia due to loss of
proprioception, the loss of sensitivity to the positions of joint and body parts. This is generally caused by dysfunction of the
dorsal columns
Dorsal (from Latin ''dorsum'' ‘back’) may refer to:
* Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism
* Dorsal, positioned on top of an aircraft's fuselage
* Dorsal co ...
of the spinal cord, because they carry proprioceptive information up to the brain. In some cases, the cause of sensory ataxia may instead be dysfunction of the various parts of the brain that receive positional information, including the cerebellum,
thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all direct ...
, and
parietal lobes.
Sensory ataxia presents itself with an unsteady "stomping" gait with heavy
heel strikes, as well as a postural instability that is usually worsened when the lack of proprioceptive input cannot be compensated for by
visual input, such as in poorly lit environments.
Physicians can find evidence of sensory ataxia during
physical examination by having patients stand with their feet together and
eyes shut. In affected patients, this will cause the instability to worsen markedly, producing wide oscillations and possibly a fall; this is called a positive
Romberg's test. Worsening of the finger-pointing test with the eyes closed is another feature of sensory ataxia. Also, when patients are standing with arms and hands extended toward the physician, if the eyes are closed, the patients' fingers tend to "fall down" and then be restored to the horizontal extended position by sudden muscular contractions (the "ataxic hand").
Vestibular
The term vestibular ataxia is used to indicate ataxia due to dysfunction of the
vestibular system, which in acute and unilateral cases is associated with prominent
vertigo,
nausea, and
vomiting. In slow-onset, chronic bilateral cases of vestibular dysfunction, these characteristic manifestations may be absent, and
dysequilibrium
A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness, or wooziness, or having a sensation of movement, spinning, or floating. Balance ...
may be the sole presentation.
Causes
The three types of ataxia have overlapping causes, so can either coexist or occur in isolation. Cerebellar ataxia can have many causes despite normal neuroimaging.
Focal lesions
Any type of focal lesion of the
central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...
(such as
stroke
A stroke is a disease, medical condition in which poor cerebral circulation, blood flow to the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemorr ...
,
brain tumor
A brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and seco ...
,
multiple sclerosis, inflammatory
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thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all direct ...
or
parietal lobe); or vestibular if in the vestibular system (including the vestibular areas of the
cerebral cortex
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting o ...
).
Exogenous substances (metabolic ataxia)
Exogenous substances that cause ataxia mainly do so because they have a depressant effect on central nervous system function. The most common example is
ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...
(alcohol), which is capable of causing reversible cerebellar and vestibular ataxia. Chronic intake of
ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...
causes atrophy of the
cerebellum by oxidative and endoplasmic reticulum stresses induced by
thiamine deficiency.
Other examples include various prescription drugs (e.g. most
antiepileptic drugs
Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of b ...
have cerebellar ataxia as a possible
adverse effect), Lithium level over 1.5mEq/L,
synthetic cannabinoid HU-211 ingestion
and various other medical and recreational drugs (e.g.
ketamine
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppress ...
,
PCP or
dextromethorphan
Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with b ...
, all of which are
NMDA receptor antagonists that produce a dissociative state at high doses). A further class of pharmaceuticals which can cause short term ataxia, especially in high doses, are
benzodiazepines.
Exposure to high levels of
methylmercury, through consumption of fish with high mercury concentrations, is also a known cause of ataxia and other neurological disorders.
Radiation poisoning
Ataxia can be induced as a result of severe
acute radiation poisoning with an absorbed dose of more than 30
grays.
Vitamin B12 deficiency
Vitamin B12 deficiency may cause, among several neurological abnormalities, overlapping cerebellar and sensory ataxia. Neuropsychological symptoms may include sense loss, difficulty in
proprioception, poor balance, loss of sensation in the feet, changes in
reflexs, dementia, and
psychosis, can be reversible with treatment. Complications may include a neurological complex known as
subacute combined degeneration of spinal cord, and other neurological disorders.
Hypothyroidism
Symptoms of neurological dysfunction may be the presenting feature in some patients with
hypothyroidism. These include reversible
cerebellar ataxia
Cerebellar ataxia is a form of ataxia originating in the cerebellum. Non-progressive congenital ataxia (NPCA) is a classical presentation of cerebral ataxias.
Cerebellar ataxia can occur as a result of many diseases and may present with sympto ...
,
dementia
Dementia is a disorder which manifests as a set of related symptoms, which usually surfaces when the brain is damaged by injury or disease. The symptoms involve progressive impairments in memory, thinking, and behavior, which negatively affe ...
,
peripheral neuropathy,
psychosis and
coma. Most of the neurological complications improve completely after
thyroid hormone replacement therapy.
Causes of isolated sensory ataxia
Peripheral neuropathies may cause generalised or localised sensory ataxia (e.g. a limb only) depending on the extent of the neuropathic involvement. Spinal disorders of various types may cause sensory ataxia from the lesioned level below, when they involve the dorsal columns.
Non-hereditary cerebellar degeneration
Non-hereditary causes of cerebellar degeneration include chronic
alcohol use disorder,
head injury,
paraneoplastic and non-paraneoplastic
autoimmune ataxia,
high altitude cerebral oedema
High-altitude cerebral edema (HACE) is a medical condition in which the brain swells with fluid because of the physiological effects of traveling to a high altitude. It generally appears in patients who have acute mountain sickness and involves dis ...
,
coeliac disease,
normal pressure hydrocephalus and infectious or post-infectious
cerebellitis
Post-viral cerebellar ataxia also known as acute cerebellitis and acute cerebellar ataxia (ACA) is a disease characterized by the sudden onset of ataxia following a viral infection. The disease affects the function or structure of the cerebellum r ...
.
Hereditary ataxias
Ataxia may depend on
hereditary disorders consisting of degeneration of the cerebellum or of the spine; most cases feature both to some extent, and therefore present with overlapping cerebellar and sensory ataxia, even though one is often more evident than the other. Hereditary disorders causing ataxia include
autosomal dominant ones such as
spinocerebellar ataxia,
episodic ataxia
Episodic ataxia (EA) is an autosomal dominant disorder characterized by sporadic bouts of ataxia (severe discoordination) with or without myokymia (continuous muscle movement). There are seven types recognized but the majority are due to two recogn ...
, and
dentatorubropallidoluysian atrophy, as well as
autosomal recessive disorders such as
Friedreich's ataxia
Friedreich's ataxia (FRDA or FA) is an autosomal-recessive genetic disease that causes difficulty walking, a loss of sensation in the arms and legs, and impaired speech that worsens over time. Symptoms generally start between 5 and 20 year ...
(sensory and cerebellar, with the former predominating) and
Niemann Pick disease,
ataxia-telangiectasia (sensory and cerebellar, with the latter predominating),autosomal recessive spinocerebellar ataxia-14 and
abetalipoproteinaemia
Abetalipoproteinemia (also known as: Bassen-Kornzweig syndrome, microsomal triglyceride transfer protein deficiency disease, MTP deficiency, and betalipoprotein deficiency syndrome) is a disorder that interferes with the normal absorption of fat ...
. An example of X-linked ataxic condition is the rare
fragile X-associated tremor/ataxia syndrome or FXTAS.
Arnold–Chiari malformation (congenital ataxia)
Arnold–Chiari malformation
Chiari malformation (CM) is a structural defect in the cerebellum, characterized by a downward displacement of one or both cerebellar tonsils through the foramen magnum (the opening at the base of the skull). CMs can cause headaches, difficulty ...
is a malformation of the
brain
A brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as Visual perception, vision. I ...
. It consists of a downward displacement of the
cerebellar tonsils and the
medulla through the
foramen magnum, sometimes causing
hydrocephalus
Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary i ...
as a result of obstruction of
cerebrospinal fluid outflow.
Succinic semialdehyde dehydrogenase deficiency
Succinic semialdehyde dehydrogenase deficiency
Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a rare autosomal recessive disorder of the degradation pathway of the inhibitory neurotransmitter γ-aminobutyric acid, or GABA. The disorder has been identified in approximately 350 fa ...
is an
autosomal-
recessive gene disorder where mutations in the ALDH5A1 gene results in the accumulation of
gamma-Hydroxybutyric acid (GHB) in the body. GHB accumulates in the nervous system and can cause ataxia as well as other
neurological
Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal c ...
dysfunction.
Wilson's disease
Wilson's disease is an
autosomal-
recessive gene disorder whereby an alteration of the ATP7B gene results in an inability to properly excrete
copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pink ...
from the body.
Copper accumulates in the nervous system and liver and can cause ataxia as well as other
neurological
Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal c ...
and organ impairments.
Gluten ataxia
Gluten ataxia is an
autoimmune disease triggered by the ingestion of
gluten.
Early diagnosis and treatment with a
gluten-free diet can improve ataxia and prevent its progression. The effectiveness of the treatment depends on the elapsed time from the onset of the ataxia until diagnosis, because the death of
neurons in the cerebellum as a result of gluten exposure is irreversible.
It accounts for 40% of ataxias of unknown origin and 15% of all ataxias.
Less than 10% of people with gluten ataxia present any gastrointestinal symptom and only about 40% have intestinal damage.
This entity is classified into primary auto-immune cerebellar ataxias (PACA).
Potassium pump
Malfunction of the
sodium-potassium pump may be a factor in some ataxias. The - pump has been shown to control and set the intrinsic activity mode of
cerebellar Purkinje neurons. This suggests that the pump might not simply be a homeostatic, "housekeeping" molecule for ionic gradients; but could be a computational element in the
cerebellum and the
brain
A brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as Visual perception, vision. I ...
. Indeed, an
ouabain block of - pumps in the cerebellum of a live
mouse results in it displaying ataxia and
dystonia. Ataxia is observed for lower ouabain concentrations, dystonia is observed at higher ouabain concentrations.
Cerebellar ataxia associated with anti-GAD antibodies
Antibodies against the enzyme glutamic acid decarboxylase (GAD: enzyme changing glutamate into GABA) cause cerebellar deficits. The antibodies impair motor learning and cause behavioral deficits.
GAD antibodies related ataxia is part of the group called immune-mediated cerebellar ataxias. The antibodies induce a synaptopathy. The cerebellum is particularly vulnerable to autoimmune disorders. Cerebellar circuitry has capacities to compensate and restore function thanks to cerebellar reserve, gathering multiple forms of plasticity. LTDpathies gather immune disorders targeting long-term depression (LTD), a form of plasticity.
Diagnosis
* Imaging studies - A
CT scan or
MRI of the brain might help determine potential causes. An
MRI can sometimes show shrinkage of the cerebellum and other brain structures in people with ataxia. It may also show other treatable findings, such as a blood clot or benign tumour, that could be pressing on the cerebellum.
* Lumbar puncture (spinal tap) - A needle is inserted into the lower back (lumbar region) between two lumbar vertebrae to obtain a sample of
cerebrospinal fluid for testing.
* Genetic testing - Determines whether the mutation that causes one of the hereditary ataxic conditions is present. Tests are available for many but not all of the hereditary ataxias.
Treatment
The treatment of ataxia and its effectiveness depend on the underlying cause. Treatment may limit or reduce the effects of ataxia, but it is unlikely to eliminate them entirely. Recovery tends to be better in individuals with a single focal injury (such as
stroke
A stroke is a disease, medical condition in which poor cerebral circulation, blood flow to the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemorr ...
or a
benign tumour
A benign tumor is a mass of cells ( tumor) that does not invade neighboring tissue or metastasize (spread throughout the body). Compared to malignant (cancerous) tumors, benign tumors generally have a slower growth rate. Benign tumors have re ...
), compared to those who have a neurological degenerative condition.
A review of the management of degenerative ataxia was published in 2009.
A small number of rare conditions presenting with prominent cerebellar ataxia are amenable to specific treatment and recognition of these disorders is critical. Diseases include vitamin E deficiency, abetalipoproteinemia, cerebrotendinous xanthomatosis, Niemann–Pick type C disease, Refsum's disease, glucose transporter type 1 deficiency, episodic ataxia type 2, gluten ataxia, glutamic acid decarboxylase ataxia. Novel therapies target the RNA defects associated with cerebellar disorders, using in particular anti-sense oligonucleotides.
The movement disorders associated with ataxia can be managed by pharmacological treatments and through
physical therapy and
occupational therapy to reduce
disability
Disability is the experience of any condition that makes it more difficult for a person to do certain activities or have equitable access within a given society. Disabilities may be cognitive, developmental, intellectual, mental, physical, ...
.
Some drug treatments that have been used to control ataxia include:
5-hydroxytryptophan
5-Hydroxytryptophan (5-HTP), also known as oxitriptan, is a naturally occurring amino acid and chemical precursor as well as a metabolic intermediate in the biosynthesis of the neurotransmitter serotonin.
Uses
5-HTP is sold over the cou ...
(5-HTP),
idebenone,
amantadine
Amantadine, sold under the brand name Gocovri among others, is a medication used to treat dyskinesia associated with parkinsonism and influenza caused by type A influenzavirus, though its use for the latter is no longer recommended due to wid ...
,
physostigmine,
L-carnitine
Carnitine is a quaternary ammonium compound involved in metabolism in most mammals, plants, and some bacteria. In support of energy metabolism, carnitine transports long-chain fatty acids into mitochondria to be oxidized for energy production, an ...
or derivatives,
trimethoprim/sulfamethoxazole,
vigabatrin
Vigabatrin, brand name Sabril, is a medication used to treat epilepsy. It became available as a generic medication in 2019.
It works by inhibiting the breakdown of γ-aminobutyric acid (GABA). It is also known as γ-vinyl-GABA, and is a stru ...
,
phosphatidylcholine,
acetazolamide,
4-aminopyridine,
buspirone, and a combination of
coenzyme Q10 and
vitamin E.
Physical therapy requires a focus on adapting activity and facilitating
motor learning for retraining specific functional motor patterns.
A recent systematic review suggested that physical therapy is effective, but there is only moderate evidence to support this conclusion.
The most commonly used physical therapy interventions for cerebellar ataxia are vestibular habituation,
Frenkel exercises,
proprioceptive neuromuscular facilitation (PNF), and balance training; however, therapy is often highly individualized and gait and coordination training are large components of therapy.
Current research suggests that, if a person is able to walk with or without a
mobility aid, physical therapy should include an exercise program addressing five components: static balance, dynamic balance, trunk-limb coordination, stairs, and
contracture prevention. Once the physical therapist determines that the individual is able to safely perform parts of the program independently, it is important that the individual be prescribed and regularly engage in a supplementary home exercise program that incorporates these components to further improve long term outcomes. These outcomes include balance tasks, gait, and individual activities of daily living. While the improvements are attributed primarily to changes in the brain and not just the hip or ankle joints, it is still unknown whether the improvements are due to adaptations in the cerebellum or compensation by other areas of the brain.
Decomposition, simplification, or slowing of multijoint movement may also be an effective strategy that therapists may use to improve function in patients with ataxia.
Training likely needs to be intense and focused—as indicated by one study performed with stroke patients experiencing limb ataxia who underwent intensive upper limb retraining.
Their therapy consisted of
constraint-induced movement therapy
Constraint-induced movement therapy (CI, CIT, or CIMT) is a form of rehabilitation therapy that improves upper extremity function in stroke and other central nervous system damage patients by increasing the use of their affected upper limb. which resulted in improvements of their arm function.
Treatment should likely include strategies to manage difficulties with everyday activities such as walking. Gait aids (such as a cane or walker) can be provided to decrease the risk of falls associated with impairment of
balance or poor
coordination. Severe ataxia may eventually lead to the need for a
wheelchair
A wheelchair is a chair with wheels, used when walking is difficult or impossible due to illness, injury, problems related to old age, or disability. These can include spinal cord injuries ( paraplegia, hemiplegia, and quadriplegia), ce ...
. To obtain better results, possible coexisting motor deficits need to be addressed in addition to those induced by ataxia. For example, muscle weakness and decreased endurance could lead to increasing fatigue and poorer movement patterns.
There are several assessment tools available to therapists and health care professionals working with patients with ataxia. The
International Cooperative Ataxia Rating Scale (ICARS) is one of the most widely used and has been proven to have very high reliability and validity.
Other tools that assess motor function, balance and coordination are also highly valuable to help the therapist track the progress of their patient, as well as to quantify the patient's functionality. These tests include, but are not limited to:
* The
Berg Balance Scale
The Berg Balance Scale (or BBS) is a widely used clinical test of a person's static and dynamic balance abilities, named after Katherine Berg, one of the developers. For functional balance tests, the BBS is generally considered to be the gold sta ...
* Tandem Walking (to test for
Tandem gaitability)
* Scale for the Assessment and Rating of Ataxia (SARA)
* tapping tests – The person must quickly and repeatedly tap their arm or leg while the therapist monitors the amount of
dysdiadochokinesia.
*
finger-nose testing – This test has several variations including finger-to-therapist's finger, finger-to-finger, and alternate nose-to-finger.
Other uses
The term "ataxia" is sometimes used in a broader sense to indicate lack of coordination in some physiological process. Examples include optic ataxia (lack of coordination between visual inputs and hand movements, resulting in inability to reach and grab objects) and ataxic respiration (lack of coordination in respiratory movements, usually due to dysfunction of the respiratory centres in the
medulla oblongata). Optic ataxia may be caused by lesions to the posterior parietal cortex, which is responsible for combining and expressing positional information and relating it to movement. Outputs of the posterior parietal cortex include the spinal cord, brain stem motor pathways, pre-motor and pre-frontal cortex, basal ganglia and the cerebellum. Some neurons in the posterior parietal cortex are modulated by intention. Optic ataxia is usually part of
Balint's syndrome, but can be seen in isolation with injuries to the superior parietal lobule, as it represents a disconnection between visual-association cortex and the frontal premotor and motor cortex.
See also
*
Ataxic cerebral palsy
Ataxic cerebral palsy is clinically in approximately 5–10% of all cases of cerebral palsy, making it the least frequent form of cerebral palsy diagnosed. Ataxic cerebral palsy is caused by damage to cerebellar structures, differentiating it from ...
*
Locomotor ataxia
*
Bruns apraxia
National Ataxia Foundation
References
Further reading
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External links
{{Authority control
Symptoms and signs: Nervous system
Stroke