Editor-In-Chief: C. Michael Gibson, M.S., M.D. 
Astasia-abasia refers to the inability to either stand or walk in a normal manner. Patients exhibit an unusual and dramatic gait disturbance, lurching wildly in various directions and falling only when a nearby physician, family member, or soft object will catch them.
Astasia refers to the inability to maintain station (stand upright) unassisted.
Abasia refers to lack of motor coordination in walking. The term literally means that the base of gait (the lateral distance between the two feet) is inconstant or unmeasurable. When seen in conversion disorder, the gait is bizarre and is not suggestive of a specific organic lesion: often the patient sways wildly and nearly falls, recovering at the last moment.
However, an acquired total inability to stand and walk can be seen in true neurological diseases, including stroke, Parkinson disease, damage to the cerebellum, and many others.
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