Department of Physical Therapy, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands.
Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Limburg, The Netherlands.
PeerJ. 2022 Jul 22;10:e13752. doi: 10.7717/peerj.13752. eCollection 2022.
Instrumented treadmills have become more mainstream in clinical assessment of gait disorders in children, and are increasingly being applied as an alternative to overground gait analysis. Both approaches differ in multiple elements of set-up (, overground versus treadmill, Pug-in Gait versus Human Body Model-II), workflow (, limited amount of steps versus many successive steps) and post-processing of data (, different filter techniques). These individual elements have shown to affect gait. Since the approaches are used in parallel in clinical practice, insight into the compound effect of the multiple different elements on gait is essential. This study investigates whether the outcomes of two approaches for 3D gait analysis are interchangeable in typically developing children.
Spatiotemporal parameters, sagittal joint angles and moments, and ground reaction forces were measured in typically developing children aged 3-17 years using the overground (overground walking, conventional lab environment, Plug-In Gait) and treadmill (treadmill walking in virtual environment, Human Body Model-II) approach. Spatiotemporal and coefficient of variation parameters, and peak values in kinematics and kinetics of both approaches were compared using repeated measures tests. Kinematic and kinetic waveforms from both approaches were compared using statistical parametric mapping (SPM). Differences were quantified by mean differences and root mean square differences.
Children walked slower, with lower stride and stance time and shorter and wider steps with the treadmill approach than with the overground approach. Mean differences ranged from 0.02 s for stride time to 3.3 cm for step width. The patterns of sagittal kinematic and kinetic waveforms were equivalent for both approaches, but significant differences were found in amplitude. Overall, the peak joint angles were larger during the treadmill approach, showing mean differences ranging from 0.84° (pelvic tilt) to 6.42° (peak knee flexion during swing). Mean difference in peak moments ranged from 0.02 Nm/kg (peak knee extension moment) to 0.32 Nm/kg (peak hip extension moment), showing overall decreased joint moments with the treadmill approach. Normalised ground reaction forces showed mean differences ranging from 0.001 to 0.024.
The overground and treadmill approach to 3D gait analysis yield different sagittal gait characteristics. The systematic differences can be due to important changes in the neuromechanics of gait and to methodological choices used in both approaches, such as the biomechanical model or the walkway versus treadmill. The overview of small differences presented in this study is essential to correctly interpret the results and needs to be taken into account when data is interchanged between approaches. Together with the research/clinical question and the context of the child, the insight gained can be used to determine the best approach.
仪器化跑步机在儿童步态障碍的临床评估中变得越来越主流，并且越来越多地被用作地面步态分析的替代方法。这两种方法在设置的多个元素（地面与跑步机、Pug-in Gait 与 Human Body Model-II）、工作流程（有限的步数与许多连续的步数）和数据后处理（不同的滤波技术）方面存在差异。这些单独的元素已经显示出对步态的影响。由于这两种方法在临床实践中是并行使用的，因此了解多个不同元素对步态的综合影响至关重要。本研究旨在调查在正常发育的儿童中，两种 3D 步态分析方法的结果是否可以互换。
使用地面（地面行走、常规实验室环境、Pug-in Gait）和跑步机（虚拟环境中的跑步机行走、Human Body Model-II）方法测量 3-17 岁正常发育儿童的时空参数、矢状关节角度和力矩以及地面反作用力。使用重复测量检验比较两种方法的时空和变异系数参数以及运动学和动力学的峰值。使用统计参数映射（SPM）比较两种方法的运动学和动力学波形。通过均差和均方根差来量化差异。
与地面方法相比，儿童在跑步机上行走速度较慢，步幅和站立时间较短，步幅和步宽较窄。均差范围从 0.02 秒的步幅时间到 3.3 厘米的步宽。两种方法的矢状运动学和动力学波形模式相同，但幅度存在显著差异。总体而言，在跑步机方法中，关节角度峰值较大，显示出从骨盆倾斜 0.84°到摆动时膝关节最大屈曲 6.42°的平均差异。峰值力矩的平均差异范围从 0.02 Nm/kg（膝关节最大伸展力矩）到 0.32 Nm/kg（髋关节最大伸展力矩），表明跑步机方法下关节力矩总体减小。归一化地面反作用力显示的平均差异范围从 0.001 到 0.024。
3D 步态分析的地面和跑步机方法产生不同的矢状步态特征。这些系统差异可能是由于步态神经力学的重要变化以及两种方法中使用的方法学选择（例如生物力学模型或走道与跑步机）所致。本研究中呈现的小差异概述对于正确解释结果至关重要，并且在两种方法之间交换数据时需要考虑这些差异。结合研究/临床问题和儿童的背景，获得的洞察力可用于确定最佳方法。
