Alcock Lisa, Galna Brook, Lord Sue, Rochester Lynn
Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE4 5PL, UK; Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE4 5PL, UK; Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
J Biomech. 2016 Sep 6;49(13):2763-2769. doi: 10.1016/j.jbiomech.2016.06.007. Epub 2016 Jun 15.
Tripping is a common cause of falls in older adults and people with Parkinson׳s disease (PD). Foot clearance during gait may be impaired when distracted by a dual task and thus inform trip risk. This study aimed to evaluate whether foot clearance is impaired in PD and is adversely affected by a dual task. 81 older adults and 76 PD walked at a comfortable pace for two minutes under single and dual task conditions (digit recall). Temporal spatial gait was measured using an instrumented walkway. Heel and toe trajectories were obtained bilaterally using 3-dimensional motion capture. Foot clearance was reduced in PD (p<.001) and under dual task (p<.027). The take-off (toe) gradient was reduced under dual task irrespective of group and the landing (heel) gradient was reduced in PD irrespective of task (p<.001). An increased proportion of unimodal toe distributions were observed for PD, particularly under dual task. Group differences were retained when controlling for step length (landing gradient and peak toe clearance in late swing) and gait velocity (landing gradient). Distinct differences in foot clearance were observed even in the early clinical stages of PD. Dual tasking may increase trip risk due to insufficient toe clearance (early swing) for both older adults and PD. Inadequate heel clearance (late swing) may increase falls risk in PD. Clearance deficits in PD are partially related to a reduced gait velocity and step length which may be targeted in tailored therapies. Further work is necessary to understand the mechanisms underlying this pathology-associated deficit.
绊倒在老年人和帕金森病（PD）患者中是跌倒的常见原因。当被双重任务分散注意力时，步态中的足部间隙可能会受损，从而提示绊倒风险。本研究旨在评估PD患者的足部间隙是否受损以及是否受到双重任务的不利影响。81名老年人和76名PD患者在单任务和双重任务条件下（数字回忆）以舒适的步伐行走两分钟。使用仪器化步道测量时空步态。通过三维运动捕捉双侧获取足跟和足尖轨迹。PD患者（p<0.001）和双重任务条件下（p<0.027）足部间隙减小。无论组别如何，双重任务下离地（足尖）坡度均减小，无论任务如何，PD患者着地（足跟）坡度均减小（p<0.001）。观察到PD患者单峰足尖分布比例增加，尤其是在双重任务下。在控制步长（着地坡度和摆动后期足尖间隙峰值）和步态速度（着地坡度）时，组间差异仍然存在。即使在PD的临床早期阶段，也观察到足部间隙存在明显差异。双重任务可能会增加老年人和PD患者因足尖间隙不足（摆动早期）而导致的绊倒风险。足跟间隙不足（摆动后期）可能会增加PD患者的跌倒风险。PD患者的间隙缺陷部分与步态速度和步长减小有关，这可能是针对性治疗的目标。有必要进一步开展工作以了解这种与病理相关的缺陷背后的机制。
