Abstract:
In-shoe models are required to extend the clinical application of current multisegment kinetic models of the bare foot to study the effect of foot orthoses. Work to date has only addressed marker placement for reliable kinematic analyses. The purpose of this study is to address the difficulties of recording contact forces with available sensors. Ten participants walked 5 times wearing two different types of footwear by stepping on a pressure platform (ground contact forces) while wearing in-shoe pressure sensors (foot sole contact forces). Pressure data were segmented by considering contact cells\' anteroposterior location, and were used to compute 3D moments at foot joints. The mean values and 95% confidence intervals were plotted for each device per shoe condition. The peak values and times of forces and moments were computed per participant and trial under each condition, and were compared using mixed-effect tests. Test-retest reliability was analyzed by means of intraclass correlation coefficients. The curve profiles from both devices were similar, with higher joint moments for the instrumented insoles at the metatarsophalangeal joint (~26%), which were lower at the ankle (~8%) and midtarsal (~15%) joints, although the differences were nonsignificant. Not considering frictional forces resulted in ~20% lower peaks at the ankle moments compared to previous studies, which employed force plates. The device affected both shoe conditions in the same way, which suggests the interchangeability of measuring joint moments with one or the other device. This hypothesis was reinforced by the intraclass correlation coefficients, which were higher for the peak values, although only moderate-to-good. In short, both considered alternatives have drawbacks. Only the instrumented in-soles provided direct information about foot contact forces, but it was incomplete (evidenced by the difference in ankle moments between devices). However, recording ground reaction forces offers the advantage of enabling the consideration of contact friction forces (using force plates in series, or combining a pressure platform and a force plate to estimate friction forces and torque), which are less invasive than instrumented insoles (which may affect subjects\' gait).
摘要:
需要鞋内模型来扩展当前赤脚多段动力学模型的临床应用,以研究足部矫形器的效果。迄今为止的工作仅解决了用于可靠运动学分析的标记放置问题。这项研究的目的是解决使用可用传感器记录接触力的困难。十名参与者穿着两种不同类型的鞋类行走5次,方法是踩在压力平台(地面接触力)上,同时穿着鞋内压力传感器(脚底接触力)。通过考虑接触细胞的前后位置来分割压力数据,并用于计算脚关节的3D力矩。绘制每个装置每个鞋条件的平均值和95%置信区间。每个参与者和试验在每种条件下计算力和力矩的峰值和时间,并使用混合效应试验进行比较。通过组内相关系数分析了重测可靠性。两种设备的曲线轮廓相似,meta趾关节的器械鞋垫具有较高的关节力矩(〜26%),较低的踝关节(~8%)和骨中关节(~15%),尽管差异不显著。与以前的研究相比,不考虑摩擦力会导致踝关节力矩的峰值降低约20%。它采用了测力板。该设备以相同的方式影响了两种鞋子的状况,这表明与一个或另一个设备测量关节力矩的互换性。这一假设得到了组内相关系数的加强,峰值更高,虽然只有中等到良好。总之,这两种考虑的替代方案都有缺点。只有带仪表的鞋底提供了有关脚接触力的直接信息,但它是不完整的(由设备之间的脚踝力矩差异证明)。然而,记录地面反作用力的优点是能够考虑接触摩擦力(使用串联的测力板,或结合压力平台和测力板来估计摩擦力和扭矩),其比器械鞋垫侵入性更小(可能影响受试者的步态)。