abasia

Abasia is a medical term used to describe an inability to walk or to sustain walking, typically arising from disruption of the initiation or coordination of leg movements rather than from a primary weakness of the leg muscles. It is not a single disease but a syndrome that can occur in various neurological and psychiatric contexts.

There are two broad often-cited forms. Organic or true abasia refers to gait disturbance due to identifiable neurological or structural problems affecting motor control, coordination, or sensory integration, such as stroke, cerebellar disease, spinal cord lesions, or neuropathies. Functional or psychogenic abasia describes gait disturbance that arises without an obvious organic cause, commonly categorized under conversion or functional movement disorders; in these cases strength and sensation may be preserved, but the patient cannot walk in a typical, coordinated manner. The term astasia-abasia has historically been used to describe dramatic, bizarre, and inconsistent gait disturbances seen in some functional disorders, where standing may be possible but walking is severely impaired or nonreproducible.

Clinical features vary by cause. Organic abasia may accompany other neurological signs such as weakness, ataxia, or sensory loss, whereas functional abasia often presents with inconsistent gait patterns, incongruous movements, and variability over time that may improve with distraction or therapeutic suggestion. Diagnosis involves a thorough neurological examination, imaging or laboratory studies to identify an underlying lesion, and careful assessment to distinguish true motor impairment from functional disturbance.

Treatment focuses on addressing the underlying cause: medical or surgical management for organic cases, and multidisciplinary rehabilitation, physical therapy, and psychotherapy for functional forms. Prognosis is highly dependent on etiology and response to therapy.