Lower Limb Muscle Activation Times of Stroke Patients Who Failed the Sit-to-Stand Task

Abstract

[Purpose] The purpose of this study was to determine the differences in electromyographic activities of hemiplegic stroke patients who succeeded and failed the sit-to-stand (STS) during the recovery phase. [Participants and Methods] Twenty stroke patients who succeeded in the STS, and 20 stroke patients who failed in the STS participated in this study. Leg muscle activation times from the time of seat-off during the STS were analyzed using surface electromyography. The differences between the groups were compared. [Results] The tibialis anterior, rectus femoris and biceps femoris activated before seat-off in both groups. However, in the failed group the gastrocnemius also activated before seat-off. Activation of the gastrocnemius was significantly earlier than in the success group. Furthermore, in the failure group, the activation of the muscles of the hip and ankle joints occurred almost at the same times. [Conclusion] These results suggest that the cause of stroke patients failing the STS is these abnormal muscle activation patterns.