Wilson James Richard, Asfour Shihab, Abdelrahman Khaled Zakaria, Gailey Robert
College of Engineering, University of Miami, Coral Gables, Florida 33124-0623, USA.
Prosthet Orthot Int. 2009 Sep;33(3):218-29. doi: 10.1080/03093640903107998.
We present a new methodology to measure the running biomechanics of amputees. This methodology combines the use of a spring-mass model and symmetry index, two standard techniques in biomechanics literature, but not yet used in concert to evaluate amputee biomechanics. The methodology was examined in the context of a pilot study to examine two transtibial amputee sprinters and showed biomechanically quantifiable changes for small adjustments in prosthetic prescription. Vertical ground reaction forces were measured in several trials for two transtibial amputees running at constant speed. A spring-mass model was used in conjunction with a symmetry index to observe the effect of varying prosthetic height and stiffness on running biomechanics. All spring-mass variables were significantly affected by changes in prosthetic prescription among the two subjects tested (p < 0.05). When prosthetic height was changed, both subjects showed significant differences, in Deltay(max), Deltal and contact time (t(c)) on the prosthetic limb and in k(vert) and k(leg) on the sound limb. The symmetry indices calculated for spring-mass variables were all significantly affected due to changes in prosthetic prescription for the male subject and all but the peak force (F(peak)) for the female subject. This methodology is a straight-forward tool for evaluating the effect of changes to prosthetic prescription.
我们提出了一种测量截肢者跑步生物力学的新方法。该方法结合了弹簧质量模型和对称指数的使用，这是生物力学文献中的两种标准技术，但尚未协同用于评估截肢者的生物力学。在一项初步研究中对该方法进行了检验，该研究考察了两名经胫骨截肢的短跑运动员，结果表明，对假肢处方进行小的调整会产生生物力学上可量化的变化。在几次试验中，测量了两名以恒定速度跑步的经胫骨截肢者的垂直地面反作用力。将弹簧质量模型与对称指数结合使用，以观察假肢高度和刚度的变化对跑步生物力学的影响。在测试的两名受试者中，所有弹簧质量变量均受假肢处方变化的显著影响（p < 0.05）。当假肢高度改变时，两名受试者在假肢侧的Δy(max)、Δl和接触时间（t(c)）以及健全侧的k(vert)和k(leg)方面均表现出显著差异。由于男性受试者的假肢处方变化，为弹簧质量变量计算的对称指数均受到显著影响，而女性受试者除峰值力（F(peak)）外的所有对称指数均受到显著影响。该方法是评估假肢处方变化效果的一种直接工具。
