The ability to shift weight toward the paretic leg has been considered an essential ability to restore independent walking for post-acute stroke patients. However, few data are available regarding the relationship between the weight-shift ability and gait performance. No clear mechanism has been provided as to why and how the weight-shift ability improves walking performance in stroke patients. We therefore investigated changes in the weight-shift ability and kinematic and kinetic parameters of walking gait in post-stroke patients during rehabilitation. Eight male inpatients undergoing rehabilitation for moderate hemiplegia participated in this study. Measurements were taken every 4 weeks from when the participants were able to walk at least 10 m until they were discharged from the hospital. Our results demonstrated a significant overall correlation between the weight-shift ability and walking velocity, indicating that the improvement in the weight-shift ability toward the paretic leg by lateral tilting of the thorax is fundamentally important to improve walking velocity. We also found that the upward impulse and vertical ground reaction force exerted by the paretic leg were significantly correlated with the walking velocity to cope with the downward impulse due to gravity and to allow sufficient time to swing the non-paretic leg forward during walking. Therefore, improvement in the weight-shift ability is crucial for restoration of walking velocity. We believe that weight-shift training for the paretic leg while instructing the patients to laterally tilt the thorax should be advocated as an effective protocol during rehabilitation of post-acute stroke inpatients.
Keywords: Stroke; biomechanics; gait analysis; hemiplegia; rehabilitation.