École de Kinésiologie et des Sciences de l'Activité Physique, Université de Montréal, Campus Laval, 1700 rue Jacques Tétreault, Laval, QC H7N 0B6, Canada.
Institut de Génie Biomédical, Université de Montréal, Campus Laval, 1700 rue Jacques Tétreault, Laval, QC H7N 0B6, Canada.
Clin Biomech (Bristol). 2021 Jun;86:105390. doi: 10.1016/j.clinbiomech.2021.105390. Epub 2021 May 23.
Foot orthoses are commonly used to correct for foot alterations and especially address excessive foot pronation in individuals with flatfeet. In recent years, 3D printing has taken a key place in orthotic manufacturing processes as it offers more options and can be patient specific. Hence, the purpose of this study was to evaluate whether stiffness of 3D printed foot orthoses and a newly designed rearfoot posting have an effect on lower limb kinematics and kinetics in individuals with flatfeet.
Nineteen patients with flexible flatfeet were provided two pairs of customized 3D printed ¾ length orthotics. Foot orthoses were of different stiffness and could feature a rearfoot posting, consisting of 2-mm carbon fiber plate. Lower limb kinematics and kinetics were computed using a multi-segment foot model. One-way ANOVAs using statistical non-parametric mapping, refined by effect sizes, were performed to determine the magnitude of the effect between conditions.
Foot orthoses stiffness had little effect on midfoot and forefoot biomechanics. Reductions in midfoot eversion and forefoot abduction were observed during short periods of stance with rigid foot orthoses. Adding the posting had notable effects on rearfoot kinematics and on the ankle and knee kinetics in the frontal plane; it significantly reduced the eversion angle and inversion moment at the ankle, and increased the knee abduction moment.
Using an anti-pronator component is more effective than increasing foot orthoses stiffness to observe a beneficial impact of foot orthoses on the control of excessive foot pronation in individuals with flatfeet.
足部矫形器常用于矫正足部畸形，特别是针对扁平足患者过度足内旋的情况。近年来，3D 打印在矫形制造工艺中占据了重要地位，因为它提供了更多的选择，并且可以针对患者进行定制。因此，本研究的目的是评估 3D 打印足矫形器和新设计的后跟固定对扁平足患者下肢运动学和动力学的影响。
19 名柔性扁平足患者提供了两副定制的 3D 打印 3/4 长度矫形器。矫形器的硬度不同，并且可以在后跟处安装由 2 毫米碳纤维板组成的后跟固定装置。使用多节段足部模型计算下肢运动学和动力学。使用单向方差分析（ANOVA）结合统计非参数映射，通过效应大小进行细化，以确定条件之间的效应大小。
足矫形器的硬度对中足和前足生物力学的影响较小。在刚性足矫形器的短时间站立期间，观察到中足外翻和前足外展减少。添加后跟固定装置对后足运动学以及额状面的踝关节和膝关节动力学有显著影响；它显著降低了踝关节的外翻角度和内翻力矩，增加了膝关节的外展力矩。
使用抗旋前组件比增加足矫形器的硬度更能有效地观察到足矫形器对扁平足患者过度足内旋控制的有益影响。
