0071643192.pdf

Sensory ataxia:

■ Failure of transmission of proprioception to the CNS via peripheral nerves,

dorsal columns or cerebellar input tract

CAUSES

Common causes of ataxia are listed in Table 15.11.

SYMPTOMS/EXAM

■ Patients may complain of difficulty ambulating, weakness, or falls.

■ Ataxia that is worse with loss of visual input (eg, walking in the dark) =

sensory ataxia.

■ The exam should focus on differentiating motor from sensory ataxia.

■ The classic cerebellar gaitis wide based with unsteady and irregular steps.

■ Asensory ataxic gaitis characterized by abrupt movement of legs and

slapping impact of feet with each step.

■ Cerebellar function testing: Observe patient perform smooth, voluntary

movements, and rapidly alternating movements.

■ Romberg test: Worsened unsteadiness with eyes closed (loss of visual input)

is suggestive of sensory ataxia.

DIAGNOSIS

Diagnosis is primarily made via history and physical exam.

TREATMENT

Define underlying cause. Treatment is directed toward primary disease process.

VERTIGO

Vertigo is defined as the perception of movement where no movement exists.

Vertigo is typically categorized as central or peripheral.

Central Vertigo

CAUSES

Results from disorders affecting the brainstem and cerebellum

■ Cerebellar hemorrhage, tumor or infarct

■ Vertebrobasilar insufficiency

NEUROLOGY

TABLE 15.11. Causes of Ataxia

GROUP EXAMPLE

Drug intoxications Ethanol, dilantin toxicity

Metabolic disorders Hyponatremia

Peripheral neuropathy Alcoholic peripheral neuropathy

Vestibulopathy Meniere disease

Cerebellar disorder Infarction, mass

Posterior column disorder Vitamin B 12 deficiency