Walking on a Vertically Oscillating Platform with Simulated Gait Asymmetry

Abstract

Asymmetric gait is associated with pain, injury, and reduced stability in patient populations. Data from side by side walking suggest that unintentional synchronization with an external cue may reduce gait asymmetry. Two types of asymmetric gait were examined here: (1) mass imbalance between limbs to simulate single limb amputation and (2) restriction of plantarflexion during toe-off to simulate reduced propulsion from neurological impairment. Twenty-five healthy participants walked normally and with simulated gait asymmetry on a custom-designed treadmill that oscillated in the vertical direction via pneumatic actuation (amplitude: 2 cm, frequency: participant’s preferred step frequency). Swing Time Asymmetry (STA) and Phase Coordination Index (PCI) both increased significantly with the application of unilateral mass and plantarflexion restriction (p < 0.001). However, walking with simulated asymmetry did not alter unintentional synchronization with the treadmill motion. Further, oscillation of the treadmill did not improve STA or PCI while walking with simulated asymmetry. Analysis of synchronized step clusters using the Weibull survival function revealed that synchronization with the platform persisted for longer durations when compared with data from side by side walking. These results suggest that walking on a vertically oscillating surface may not be an effective approach for improving gait asymmetry.

The effect of transcranial direct current stimulation on bilateral asymmetry and joint angles of the lower limb for females when crossing obstacles

“…Previous research has suggested that unilateral limb dominance caused by differences in the dominant functions upon the two hemispheres of the brain is one of the causes of bilateral asymmetry in normal gait [ 11 ], gait asymmetry associated with natural functional differences between the two limbs can also lead to bilateral musculoskeletal mass and strength imbalances [ 13 ]. Simultaneously, greater lower limb asymmetry necessitates more energy to walk, and prolonged asymmetrical walking can place additional strain on the lower limb joints and accelerate degenerative joint changes [ 14 ]. Therefore, gait asymmetry is an important factor affecting walking efficiency and safety, reduced lower limb asymmetry allows the limb to make faster transitions in response to disturbances, lowering the risk of falling.…”