Shirota Camila, Simon Ann M, Kuiken Todd A
Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA.
Center for Bionic Medicine, Rehabilitation Institute of Chicago, 345 E. Superior St., room 1309, Chicago, IL, 60611, USA.
J Neuroeng Rehabil. 2015 Sep 9;12:79. doi: 10.1186/s12984-015-0067-8.
Recovering from trips is challenging for transfemoral amputees, and attempts often result in falls. Better understanding of the effects of the sensory-motor deficits brought by amputation and the functional limitations of prosthetic devices could help guide therapy and fall prevention mechanisms in prostheses. However, how transfemoral amputees attempt to recover from trips on the sound and prosthesis sides throughout swing phase is poorly understood.
We tripped eight able-bodied subjects and eight unilateral transfemoral amputees wearing their prescribed prostheses. The protocol consisted of six repetitions of 6 and 4 points throughout swing phase, respectively. We compared recovery strategies in able-bodied, sound side and prosthesis side limbs. The number of kinematic recovery strategies used, when they were used throughout swing phase, and kinematic characteristics (tripped limb joint angles, bilateral trochanter height and time from foot arrest to foot strike) of each strategy were compared across limb groups. Non-parametric statistical tests with corrections for post-hoc tests were used.
Amputees used the same recovery strategies as able-bodied subjects on both sound and prosthesis sides, although not all subjects used all strategies. Compared to able-bodied subjects, amputees used delayed-lowering strategies less often from 30-60 % of swing phase on the sound side, and from 45-60 % of swing phase on the prosthesis side. Within-strategy kinematic differences occurred across limbs; however, these differences were not consistent across all strategies. Amputee-specific recovery strategies-that are not used by control subjects-occurred following trips on both the sound and prosthesis sides in mid- to late swing.
Collectively, these results suggest that sensory input from the distal tripped leg is not necessary to trigger able-bodied trip recovery strategies. In addition, the differences between sound and prosthesis side recoveries indicate that the ability of the support leg might be more critical than that of the tripped leg when determining the response to a trip. The outcomes of this study have implications for prosthesis control, suggesting that providing correct and intuitive real-time selection of typical able-bodied recovery strategies by a prosthetic device when it is the tripped and the support limb could better enable balance recovery and avoid falls.
对于经股截肢者而言，从绊倒中恢复过来具有挑战性，而且尝试恢复时常常会摔倒。更好地了解截肢带来的感觉运动缺陷以及假肢装置的功能限制，有助于指导治疗和假肢的防摔倒机制。然而，对于经股截肢者在整个摆动期如何在健全侧和假肢侧尝试从绊倒中恢复过来，我们知之甚少。
我们绊倒了八名身体健全的受试者以及八名单侧经股截肢者，这些截肢者佩戴着他们的定制假肢。该方案包括在整个摆动期分别对6个点和4个点进行六次重复测试。我们比较了健全者、健全侧肢体和假肢侧肢体的恢复策略。比较了各肢体组使用的运动恢复策略的数量、在整个摆动期使用这些策略的时间，以及每种策略的运动学特征（绊倒肢体的关节角度、双侧转子高度以及从脚制动到脚着地的时间）。使用了经过事后检验校正的非参数统计检验。
截肢者在健全侧和假肢侧使用的恢复策略与身体健全的受试者相同，尽管并非所有受试者都使用了所有策略。与身体健全的受试者相比，截肢者在健全侧摆动期30%至60%的时间内以及在假肢侧摆动期45%至60%的时间内较少使用延迟降低策略。各策略的运动学差异在不同肢体间存在；然而，这些差异在所有策略中并不一致。在摆动中期至后期，健全侧和假肢侧绊倒后出现了对照受试者未使用的特定于截肢者的恢复策略。
总体而言，这些结果表明，来自远端绊倒腿部的感觉输入对于触发健全者的绊倒恢复策略并非必要。此外，健全侧和假肢侧恢复之间的差异表明，在确定对绊倒的反应时，支撑腿的能力可能比绊倒腿的能力更为关键。本研究结果对假肢控制具有启示意义，表明当假肢作为绊倒腿和支撑腿时，通过假肢装置提供正确且直观的典型健全者恢复策略实时选择，能够更好地实现平衡恢复并避免摔倒。
Zotero 插件
