Mahon Caitlin E, Darter Benjamin J, Dearth Christopher L, Hendershot Brad D
DoD-VA Extremity Trauma and Amputation Center of Excellence, 8901 Wisconsin Ave. NW, Bethesda, MD.
Department of Rehabilitation, Walter Reed National Military Medical Center, 8901 Wisconsin Ave. NW, Bethesda, MD.
Mil Med. 2019 Jul 1;184(7-8):e281-e287. doi: 10.1093/milmed/usy424.
Temporal-spatial symmetry allows for optimal metabolic economy in unimpaired human gait. The gait of individuals with unilateral transfemoral amputation is characterized by temporal-spatial asymmetries and greater metabolic energy expenditure. The objective of this study was to determine whether temporal-spatial asymmetries account for greater metabolic energy expenditure in individuals with unilateral transfemoral amputation.
The relationship between temporal-spatial gait asymmetry and metabolic economy (metabolic power normalized by walking speed) was retrospectively examined in eighteen individuals with transfemoral amputation walking at a self-selected velocity overground. Pearson's product-moment correlations were used to assess the relationship between: (1) step time symmetry and metabolic economy and (2) step length symmetry and metabolic economy. The retrospective analysis of this data was approved by the Walter Reed National Military Medical Center Institutional Review Board and all individuals provided written consent. Additional insights on this relationship are presented through a case series describing the temporal-spatial and metabolic responses of two individuals with transfemoral amputation who completed a split-belt treadmill walking test.
For the cohort of individuals, there was no significant relationship between metabolic economy and either step time asymmetry or step length asymmetry. However, the case series showed a positive relationship between step length asymmetry and metabolic power as participants adapted to split-belt treadmill walking.
There is mixed evidence for the relationship between temporal-spatial asymmetries and metabolic energy expenditure. This preliminary study may suggest optimal metabolic energy expenditure in individuals with transfemoral amputation occurs at an individualized level of symmetry and resultant deviations incur a metabolic penalty. The results of this study support the idea that addressing only temporal-spatial gait asymmetries in individuals with transfemoral amputation through rehabilitation may not improve metabolic economy. Nevertheless, future prospective research is necessary to confirm these results and implications for clinical practice.
时空对称性有助于在正常人类步态中实现最佳代谢经济性。单侧经股骨截肢个体的步态具有时空不对称性，且代谢能量消耗更大。本研究的目的是确定时空不对称性是否导致单侧经股骨截肢个体的代谢能量消耗增加。
回顾性研究了18名经股骨截肢个体在地面以自选速度行走时，时空步态不对称性与代谢经济性（代谢功率除以步行速度）之间的关系。使用皮尔逊积差相关系数来评估以下两者之间的关系：（1）步时对称性与代谢经济性；（2）步长对称性与代谢经济性。沃尔特·里德国家军事医疗中心机构审查委员会批准了对该数据的回顾性分析，所有个体均提供了书面同意书。通过一个病例系列进一步阐述了这种关系，该病例系列描述了两名经股骨截肢个体在完成分带跑步机步行测试时的时空和代谢反应。
对于该队列个体，代谢经济性与步时不对称性或步长不对称性之间均无显著关系。然而，病例系列显示，随着参与者适应分带跑步机行走，步长不对称性与代谢功率之间呈正相关。
关于时空不对称性与代谢能量消耗之间的关系，证据并不一致。这项初步研究可能表明，经股骨截肢个体的最佳代谢能量消耗发生在个体化的对称水平，由此产生的偏差会导致代谢代价。本研究结果支持这样一种观点，即仅通过康复治疗解决经股骨截肢个体的时空步态不对称性可能无法改善代谢经济性。尽管如此，未来仍需要进行前瞻性研究来证实这些结果及其对临床实践的影响。
