Postural sway in amputees and normal subjects.

The postural sway of amputees was investigated quantitatively in fifty patients with above-the-knee amputations and in twenty-nine patients with below-the-knee amputations. The factors evaluated were: (1) the mean speed of sway: (2) the range of movement in the sagittal and coronal planes; and (3) the dependence on vision as indicated by the ratio of eyes-open to eyes-closed values. The results demonstrated that in amputees there is an increased dependence on vision for maintenance of the erect posture. Postural sway in patients with below-the-knee amputations was found to be significantly greater than that in those with above-the-knee amputations. Postural sway increased with age; but the visual dependence for the control of postural sway was independent of age.