Beretta Victor Spiandor, Vitório Rodrigo, Santos Paulo Cezar Rocha Dos, Orcioli-Silva Diego, Gobbi Lilian Teresa Bucken
São Paulo State University (Unesp), Institute of Biosciences, Posture and Gait Studies Laboratory (LEPLO), Rio Claro, Brazil; Post-Graduation Program in Movement Sciences, São Paulo State University - UNESP, Brazil.
São Paulo State University (Unesp), Institute of Biosciences, Posture and Gait Studies Laboratory (LEPLO), Rio Claro, Brazil; Post-Graduation Program in Movement Sciences, São Paulo State University - UNESP, Brazil.
Hum Mov Sci. 2019 Apr;64:12-18. doi: 10.1016/j.humov.2019.01.001. Epub 2019 Jan 9.
Different clinical subtypes of Parkinson's disease (PD) have long been recognized. Recent studies have focused on two PD subtypes: Postural Instability and Gait Difficulty (PIGD) and Tremor Dominant (TD). PIGD patients have greater difficulties in postural control in relation to TD. However, knowledge about the differences in reactive adjustment mechanisms following a perturbation in TD and PIGD is limited. This study aimed to compare reactive postural adjustments under unexpected external perturbation in TD, PIGD, and control group (CG) subjects. Forty-five individuals (15 TD, 15 PIGD, and 15 CG) participated in this study. Postural perturbation was applied by the posterior displacement of the support surface in an unexpected condition. The velocity (15 cm/s) and displacement (5 cm/s) of perturbation were the same for all participants. Center of pressure (CoP) and center of mass (CoM) were analyzed for two reactive windows after the perturbation (0-200 ms and 200-700 ms). The Bonferroni post hoc test indicated a higher range of CoP in the PIGD when compared to the CG (p = 0.021). The PIGD demonstrated greater time to recover the stable posture compared to the TD (p = 0.017) and CG (p = 0.003). Furthermore, the TD showed higher AP-acceleration peak of CoM when compared to the PIGD (p = 0.048) and CG (p = 0.013), and greater AP-acceleration range of CoM in relation to the CG (p = 0.022). These findings suggest that PD patients present worse reactive postural control after perturbation compared to healthy older individuals. CoP and CoM parameters are sensitive to understand and detect the differences in reactive postural mechanisms in PD subtypes.
帕金森病（PD）的不同临床亚型早已为人所知。最近的研究聚焦于两种PD亚型：姿势不稳和步态障碍型（PIGD）以及震颤为主型（TD）。与TD患者相比，PIGD患者在姿势控制方面存在更大困难。然而，关于TD和PIGD在受到干扰后反应性调整机制差异的了解有限。本研究旨在比较TD、PIGD和对照组（CG）受试者在意外外部干扰下的反应性姿势调整。45名个体（15名TD、15名PIGD和15名CG）参与了本研究。在意外情况下，通过支撑面的向后位移施加姿势干扰。所有参与者的干扰速度（15厘米/秒）和位移（5厘米/秒）相同。在干扰后（0 - 200毫秒和200 - 700毫秒）的两个反应窗口内分析压力中心（CoP）和质心（CoM）。Bonferroni事后检验表明，与CG相比，PIGD的CoP范围更高（p = 0.021）。与TD（p = 0.017）和CG（p = 0.003）相比，PIGD恢复稳定姿势的时间更长。此外，与PIGD（p = 0.048）和CG（p = 0.013）相比，TD的CoM前后向加速度峰值更高，并且与CG相比，TD的CoM前后向加速度范围更大（p = 0.022）。这些发现表明，与健康老年人相比，PD患者在受到干扰后表现出更差的反应性姿势控制。CoP和CoM参数对于理解和检测PD亚型中反应性姿势机制的差异很敏感。
