Ataxia

Clinic

• Recently Ataxia is used specifically to describe the symptoms of motor mismatching synchronization and balance disorder due to disorders of
  • Brain
  • Cerebellum
  • Deep sensation (proprioception)
  • Vestibular system

Types

Different pathological locations often show different characteristics.

• Sensory ataxia: Impairment of somatosensory nerve, which leads to the interruption of sensory feedback signals and therefore, the body incoordination is caused.
• Cerebellar Ataxia: Positive Romberg’s sign means that slow Walking / Rolling become mild when eyes are open and aggravated when eyes are closed.
• Trunk ataxia: Often Cerebellar vermis is involved.
• Limb ataxia: Often cerebellar hemisphere is involved. The corresponding patients often have eye tremor, low muscle tension, unclear speech, and other symptoms

Ataxia as a COD

• Ataxia is a COD, since it has a variety of Sigh / Symptoms which have a common axis, which is named cerebellum. These Sign / Symptoms arise from different pars of cerebellum and their extra cerebellar centers.
• As I explained it in more details in Nerocognitive considerations, Ultra complexity of our nervous system does not let neuroscientists to localized Functional units Anatomically / Physiologically.
• Although it is very Tempting to isolate the functional units of nervous system, But we are not allowed to delay the treatment of patients until these physiological units are isolated.
• So TLT tries to make a model by use these functional units only by their function and dysfunction.

Entities

• Lack of voluntary coordination of muscle movements that can include
  • Gait abnormality: Balance disturbances
  • Dysarthria
  • Nystagmus
• Vertigo: Postural instability
• Unsteadiness
• Extremities In coordination / Awkwardness: Dysdiadochokinesia, Dysmetria, Peculiar writing abnormalities
• Tremor

Note

• Ataxia can be limited to one side of the body, which is referred to as hemiataxia.
• Dystaxia is a mild degree of ataxia.
• Here we have a confusing rubric, named Ataxia. Since it is used in its general them, means unbalance movements. I prefer using this rubric as a general guiding in all problems of Balance system, But for finding one or two miasm, you should add an entity to it.

Sensory Ataxia / Propioceptive ataxia

Sensory Ataxia is a form of ataxia caused not by cerebellar dysfunction. It is due to

• Loss of Sensory input / Proprioception
• Dysfunction of dorsal columns of spinal cord (Carry proprioceptive information)
• Dysfunction of various parts of brain that receive positional information, including the cerebellum, thalamus and parietal lobes.

Spinocerebellar ataxia

Truncal ataxia:

• Uncertain starts and stops
• Lateral deviations
• Unequal steps

Vestibulocerebellar ataxia

• Flocculonodular lobe is involved
• Balance disturbances
• Control of eye movements
• Postural instability
• Negative Romberg's test

Truncal ataxia

Truncal ataxia is caused by midline damage to the cerebellar vermis.

Acute cerebellar ataxia of childhood

So

there are three interactive system involved in Ataxia:

1. Propioceptive system
2. Visual / Vestibular system
3. Central system