F Yazdani, M Razeghi, S Ebrahimi
PhD, Rehabilitation Sciences Research Centre, Department of Physical Therapy, School of Rehabilitation Sc ences, Shiraz University of Medical Sciences, Shiraz, Iran.
J Biomed Phys Eng. 2020 Feb 1;10(1):93-102. doi: 10.31661/jbpe.v0i0.639. eCollection 2020 Feb.
Excessive range of adductory free moment of the ground reaction force may potentially increase the risk of lower extremity injuries by applying a higher torsional load transmitted to the proximal parts.
It was hypothesized that the free moment pattern might be different between hyper-pronated and normal feet subjects. Moreover, a correlation would exist between peak adduction free moment and peak ankle-foot complex abduction at the stance phase of walking.
In this cross sectional study, thirty female participants were divided into two groups of asymptomatic hyper-pronated and normal feet. Kinetic and kinematic data were collected using a single force plate and a six-camera motion analysis system during three successful free speed walking trials. Ensemble average curves were extracted from the time normalized individual trials of the stance phase for both free moment and peak ankle-foot complex abduction parameters.
Significant differences in peak adductory free moment, peak ankle-foot complex eversion and peak ankle-foot complex abduction were found between normal and hyper-pronated groups (4.90±0.97 Vs. 5.94±0.88, P < 0.01), (3.30±0.95 Vs. 6.28±1.47, P < 0.01) and (4.52±1.16 Vs. 8.23±2.52, P < 0.01) respectively. A significant positive correlation was found between the peak adduction free moment and peak ankle-foot complex abduction in both groups, which was more strongly positive in hyper-pronated group (r = 0.745, p < 0.01 for normal group and r = 0.900, p < 0.01 for hyper-pronated group).
As a good measure of torque which is transmitted to the lower extremity, may free moment be a useful biomechanical indicator for both clinical and research purposes.
地面反作用力内收自由力矩范围过大，可能通过向近端传递更高的扭转载荷，增加下肢受伤风险。
假设高弓足和正常足受试者之间的自由力矩模式可能不同。此外，在步行站立期，内收自由力矩峰值与踝足复合体外展峰值之间存在相关性。
在这项横断面研究中，30名女性参与者被分为无症状高弓足组和正常足组。在三次成功的自由速度步行试验中，使用单块测力板和六相机运动分析系统收集动力学和运动学数据。从站立期时间标准化的个体试验中提取自由力矩和踝足复合体外展峰值参数的总体平均曲线。
正常组和高弓足组在内收自由力矩峰值、踝足复合体外翻峰值和踝足复合体外展峰值方面存在显著差异（分别为4.90±0.97对5.94±0.88，P<0.01），（3.30±0.95对6.28±1.47，P<0.01）和（4.52±1.16对8.23±2.52，P<0.01）。两组内收自由力矩峰值与踝足复合体外展峰值之间均存在显著正相关，高弓足组的相关性更强（正常组r = 0.745，p<0.01；高弓足组r = 0.900，p<0.01）。
作为传递到下肢的扭矩的良好度量，自由力矩可能是临床和研究目的有用的生物力学指标。
