Increased Trailing Limb Angle is Associated with Regular and Stable Trunk Movements in Patients with Hemiplegia

In post-stroke patients, shifts in the center of gravity may affect joint movement patterns of the paraplegic lower limb during walking. The impact of changes in ankle dorsiflexion angle and trailing limb angle due to slight weight-shifting is unknown. This study aimed to investigate the effect of the abovementioned parameters on gait characteristics measured by trunk acceleration.

During walking, the ankle dorsiflexion angle and trailing limb angle were assessed using two-dimensional motion analysis. Shifts in the center of gravity were assessed to evaluate symmetry, regularity, and sway of trunk movements by calculating the harmonic ratio, autocorrelation coefficient, and root mean square using a wearable trunk accelerometer.

Ankle dorsiflexion angle showed a significant negative correlation with the root mean square of the anteroposterior axis (r = -0.460, p = 0.005). Trailing limb angle was significantly correlated with the autocorrelation coefficient of the vertical axis (r = 0.585, p < 0.001) and root mean square of the vertical (r = -0.579, p < 0.001), mediolateral (r = -0.474, p = 0.004), and anteroposterior axes (r = -0.548, p = 0.001). Trailing limb angle was a significant predictor (autocorrelation coefficient vertical axis, p = 0.001; root mean square vertical axis, p = 0.001; mediolateral axis, p = 0.007; anteroposterior axis, p = 0.001).

Trailing limb angle can indicate the acquisition of forward propulsion during walking; an increase in it may contribute to improvements of the regular vertical movement ability and stability of the center of gravity sway.