Schache Anthony G, Baker Richard, Vaughan Christopher L
Murdoch Childrens Research Institute and Hugh Williamson Gait Laboratory, Royal Childrens Hospital, Flemington Road, Parkville, Melbourne, Victoria 3052, Australia.
J Biomech. 2007;40(1):9-19. doi: 10.1016/j.jbiomech.2005.12.003. Epub 2006 Jan 26.
When comparing previous studies that have measured the three-dimensional moments acting about the lower limb joints (either external moments or opposing internal joint moments) during able-bodied adult gait, significant variation is apparent in the profiles of the reported transverse plane moments. This variation cannot be explained on the basis of adopted convention (i.e. external versus internal joint moment) or inherent variability in gait strategies. The aim of the current study was to determine whether in fact the frame in which moments are expressed has a dominant effect upon transverse plane moments and thus provides a valid explanation for the observed inconsistency in the literature. Kinematic and ground reaction force data were acquired from nine able-bodied adult subjects walking at a self-selected speed. Three-dimensional hip, knee and ankle joint moments during gait were calculated using a standard inverse dynamics approach. In addition to calculating internal joint moments, the components of the external moment occurring in the transverse plane at each of the lower limb joints were calculated to determine their independent effects. All moments were expressed in both the laboratory frame (LF) as well as the anatomical frame (AF) of the distal segment. With the exception of the ankle rotation moment in the foot AF, lower limb transverse plane joint moments during gait were found to display characteristic profiles that were consistent across subjects. Furthermore, lower limb transverse plane joint moments during gait differed when expressed in the distal segment AF compared to the LF. At the hip, the two alternative reference frames produced near reciprocal joint moment profiles. The components of the external moment revealed that the external ground reaction force moment was primarily responsible for this result. Lower limb transverse plane joint moments during gait were therefore found to be highly sensitive to a change in reference frame. These findings indicate that the different transverse plane joint moment profiles during able-bodied adult gait reported in the literature are likely to be explained on this basis.
在比较以往关于测量健全成年人步态期间下肢关节处三维力矩（无论是外力矩还是相应的内关节力矩）的研究时，已报道的横断面力矩曲线存在明显差异。这种差异无法基于所采用的惯例（即外力矩与内关节力矩）或步态策略的固有变异性来解释。本研究的目的是确定实际上力矩所表达的参考系是否对横断面力矩有显著影响，从而为文献中观察到的不一致提供一个合理的解释。从九名以自定速度行走的健全成年受试者获取运动学和地面反作用力数据。使用标准的逆动力学方法计算步态期间的三维髋、膝和踝关节力矩。除了计算内关节力矩外，还计算每个下肢关节横断面处外力矩的分量，以确定其独立影响。所有力矩均在实验室参考系（LF）以及远端节段的解剖学参考系（AF）中表示。除了足部AF中的踝关节旋转力矩外，发现步态期间下肢横断面关节力矩呈现出跨受试者一致的特征曲线。此外，与LF相比，当在远端节段AF中表示时，步态期间下肢横断面关节力矩有所不同。在髋关节处，两种不同的参考系产生了近乎相反的关节力矩曲线。外力矩的分量表明，地面反作用力矩是造成这一结果的主要原因。因此，发现步态期间下肢横断面关节力矩对参考系的变化高度敏感。这些发现表明，文献中报道的健全成年人步态期间不同的横断面关节力矩曲线很可能基于此得到解释。
Zotero 插件