From the Guidelines
Ataxia is a neurological sign that indicates problems with coordination and movement control, suggesting potential damage or dysfunction in the cerebellum or its connecting pathways, and its presence warrants immediate medical attention to rule out acute neurological emergencies such as stroke. Ataxia manifests as unsteady, imprecise, or clumsy movements, often affecting walking, fine motor tasks, speech, and eye movements. The specific pattern of ataxia can help identify the underlying cause - for example, gait ataxia suggests midline cerebellar damage, while limb ataxia points to lateral cerebellar hemisphere involvement 1. Common causes of ataxia include stroke, multiple sclerosis, alcohol abuse, vitamin deficiencies (particularly B1 and E), certain medications, genetic disorders, brain tumors, and autoimmune conditions. Some key points to consider when evaluating ataxia include:
- The time course of illness, with acute onset ataxia typically referring to ataxia that develops within hours or days, and chronic ataxia defined as ataxia lasting longer than 2 months 1
- The presence of additional neurological deficits, such as weakness, hyperreflexia, spasticity, and sensory loss, which can help localize the underlying lesion 1
- The importance of careful neurological examination and imaging studies, such as MRI, in determining the underlying cause of ataxia and guiding appropriate treatment 1 When ataxia appears suddenly, it may indicate a stroke or other acute neurological emergency requiring immediate medical attention. Chronic progressive ataxia often suggests a neurodegenerative or genetic condition. Proper diagnosis and management of ataxia are crucial to improve morbidity, mortality, and quality of life outcomes.
From the Research
Definition and Classification of Ataxia
- Ataxia is defined as a lack of coordination of voluntary movement, caused by a variety of factors 2
- It can be classified by the age at onset and type (chronic or acute) 2
- Ataxia can be further categorized into different types, including vestibular, sensory, or cerebellar in origin 3
Causes and Mechanisms of Ataxia
- Ataxia can be caused by damage to several different nervous system structures, including the cerebellum and sensory structures 4
- The basic mechanism underlying ataxia is not yet fully understood, but it may be due in part to an inability to coordinate the relative activity of multiple muscles and adjust movements at a given joint for the effects of other moving joints (interaction torques) 4
- Ataxia may also be caused by ingestion of toxic substances, musculoskeletal diseases, psychogenic disorders, extrapyramidal movement disorders, peripheral neuropathies, spasticity from any cause, and epilepsy 3
Diagnosis and Management of Ataxia
- The diagnosis of ataxia involves a clinical work-up, including biochemical analyses and imaging studies 2, 5
- The correct diagnosis of ataxia is essential, as many of these disorders represent potential treatable conditions and early therapy may prevent progressive cerebellar ataxia 5
- A detailed history and neurologic examination are crucial in evaluating patients with ataxia, and proper diagnostic tests can be designed to confirm the clinical working diagnosis 6