Evaluation of a visual feedback system in gait retraining: A pilot study

Does visual augmented feedback reduce local dynamic stability while walking?

“…As mentioned below, the reduced LDS while walking with augmented feedback might be a result of 1) a reduction in gait speed, 2) a more conscious or controlled walking and 3) a consequence of the manipulation of pelvis and trunk kinematics: 1) Our results showed a decrease in gait speed (previously reported in [2]) and LDS while subjects were using the augmented feedback system. Since an emphasis on movement accuracy reduces walking speed [16], our subjects presumably walked slower because of the more conscious control of gait parameters (when adjusting actual movements with the predefined physiological movements).…”

“…Data was taken from a previously reported study [2]. In ten women (age: mean=61 years, SD=4 years) with abnormal gait patterns (caused by THR: n=2, pain in lumbar spine: n=4, pain in pectoral girdle: n=2, pain in knee joint: n=2, leg length discrepancy of 2 cm: n=1), kinematic gait data of normal walking and of walking while the subjects simultaneously received visual augmented feedback was collected.…”

“…The actual values of pelvis and trunk movements were visually presented as green axes in real-time on a Head-Mounted Display (Nikon Media Port UP300x). The subjects were briefed to oscillate the green axes (actual movements) symmetrically within red limits (predefined range of motion) which were determined previously based on reference data obtained from a healthy cohort [2]. The subjects completed the walking distance twice to get familiar to the system.…”

“…We already showed that the range of motion of the pelvis und trunk inclinations in the frontal plane improved during walking in women with several gait disorders while they were using real time visual feedback [2]. However, a recent study reported that voluntary changes of gait parameters reduce the trunk's local dynamic stability (LDS) [3] which in turn has been associated with increased risk of falling [4][5][6].…”

“…As visual augmented feedback in gait (re-) training aims to provoke such voluntary changes, the aim of the present study was to evaluate the instantaneous effect of visual augmented feedback (used in [2,7] which was applied to alter frontal pelvis and trunk kinematics) on the LDS of pelvis and trunk movements while walking. We hypothesised that the Largest Lyapunov Exponent (λ, as a measure of LDS) of pelvis and trunk trajectories will increase in women with gait disorders while receiving visual augmented feedback to correct their frontal plane pelvis und trunk kinematics.…”