Duppen Chelsea Parker, Sachdeva Nikhil, Wrona Hailey, Browner Nina, Lewek Michael D
Human Movement Science Curriculum, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
J Biomech. 2025 Jul;188:112783. doi: 10.1016/j.jbiomech.2025.112783. Epub 2025 May 26.
People with Parkinson disease (PwPD) demonstrate hypokinesia during gait initiation, marked by a decreased first step length and reduced anticipatory postural adjustment (APA) size. Effective postural control is critical for shifting from double to single limb support during gait initiation. Although PwPD are known to have impaired postural control strategies, its impact on spatial aspects of gait initiation remains unclear. This study investigated how different weight shift amplitudes onto the initial stance limb during gait initiation affect first step length, mediolateral APA size, and the ability to bring the centre of mass (COM) close to the centre of pressure (COP) for PwPD. We hypothesized that cueing for larger weight shifts would yield a larger APA, reduce the distance between COP and COM in the mediolateral direction (COM-COMx), and result in larger first steps. Eleven adults with idiopathic PD (Hoehn & Yahr Stages 1-3) were given visual biofeedback to cue weight shifts of 40, 60, and 80 % towards the initial stance limb before initiating gait. No significant difference was found between uncued and cued conditions for first step length (p = 0.210), however, cued conditions resulted in smaller mediolateral APA sizes (p < 0.001), and reduced COP-COMx compared to uncued trials (p < 0.001). A weak positive correlation was found between mediolateral APA size and first step length (ρ = 0.236, p = 0.005), suggesting a very small role of APAs in first step length amplitude in this population. In conclusion, cueing for increased weight shift amplitude improves stability but does not enhance first step length during gait initiation for PwPD.
帕金森病患者（PwPD）在步态起始时表现出运动迟缓，其特征为第一步步长减小和预期姿势调整（APA）幅度降低。有效的姿势控制对于步态起始时从双腿支撑转变为单腿支撑至关重要。尽管已知PwPD的姿势控制策略受损，但其对步态起始空间方面的影响仍不清楚。本研究调查了步态起始时向初始支撑腿施加不同幅度的体重转移如何影响PwPD的第一步步长、内外侧APA幅度以及使重心（COM）靠近压力中心（COP）的能力。我们假设提示更大幅度的体重转移会产生更大的APA，减小内外侧方向上COP与COM之间的距离（COM-COMx），并导致更大的第一步步长。11名特发性帕金森病成人患者（Hoehn & Yahr分期1-3期）在开始步态前接受视觉生物反馈，以提示向初始支撑腿进行40%、60%和80%的体重转移。在无提示和有提示条件下，第一步步长未发现显著差异（p = 0.210），然而，与无提示试验相比，有提示条件下的内外侧APA幅度更小（p < 0.001），且COP-COMx减小（p < 0.001）。在内外侧APA幅度与第一步步长之间发现了微弱的正相关（ρ = 0.236，p = 0.005），表明在该人群中APA对第一步步长幅度的作用非常小。总之，对于PwPD，提示增加体重转移幅度可提高稳定性，但在步态起始时不会增加第一步步长。
