Dynamic Balance Control during Gait in Patients with Post-stroke Hemiplegia

The incidence of falls in patients with stroke is high, which may be related to their posture during hemiplegic gait. However, no study has examined the relationship between the dynamic stability of the center of mass (COM) and postural evaluation during hemiplegic gait. This study investigated the differences in dynamic stability of the COM during gait between patients with stroke and hemiplegia and healthy older adults, based on the margin of stability (MOS).

The MOS was calculated during gait in 22 patients with hemiplegia (hemiplegic group: 10 men/12 women) and 24 healthy older adults (healthy group: 12 men/12 women) to evaluate the dynamic stability of the COM. An unpaired t-test was conducted to examine the differences in the MOS, spatiotemporal gait parameters, and joint angles.

Regarding spatiotemporal parameters, the hemiplegic group demonstrated a significantly slower walking velocity, shorter step length, and wider step width than the healthy group. They also had significantly larger MOS in the anteroposterior (AP) and mediolateral (ML) directions than the healthy group. The hemiplegic group had significantly reduced lateral trunk flexion, smaller hip flexion angle, larger hip abduction angle, and smaller knee flexion angle.

Compared with healthy adults, patients with hemiplegia exhibited larger MOS in both the AP and ML directions. These findings suggest the adoption of conservative, compensatory gait strategies to maintain safety during gait, rather than a reflection of superior balance control.