Analysis for Sit-to-Stand Performance According to the Angle of Knee Flexion in Individuals with Hemiparesis

[Purpose] Sit-to-stand (STS) is one of the important functional tasks people perform throughout the day. This study investigated whether varying angles of knee flexion affect STS patterns in individuals with hemiparesis by using a foot plantar pressure measurement system. [Methods] Fifteen stroke patients with hemiparesis participated for this study. They performed sit-to-stand with three angles of knee flexion (70°, 90°, and 110°). We measured the trajectory of the center of pressure, peak plantar pressure, and symmetry index using a Mat-scan system (Tekscan, South Boston, MA, USA). [Results] As a result, we found that there were significant differences among the three angle conditions (trajectory of center of pressure, peak plantar pressure on the affected side, and symmetry index). However, there was no significant difference in peak pressure according to the knee flexion on the unaffected side. [Conclusion] In the current study, we found that stroke patients with hemiparesis had a compensated STS pattern according to knee flexion angles. This indicates that the peak value of plantar pressure increased and that the trajectory of the center of pressure widened as the angle of knee flexion increased. We also suggest that hemiparesis patients should be more concerned about proper knee angle for symmetrical STS pattern.