sway, postural

sway, postural

Forward and backward movement of the body with motion occurring around the ankle joints when the feet are fixed on the floor. Backward sway is controlled by the anterior tibialis, quadriceps, and abdominal muscles; forward sway is controlled by the gastrocnemius, hamstring, and paraspinal muscles. Patients with lesions of the dorsal and lateral columns of the central nervous system exhibit increased postural sway when they close their eyes and may fall down if they are not supported.
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